The main function of the national park is to preserve the nature.

As defined by Nature Conservation Act from 16.04.2004 (art. 2, (1)) the conservation of nature means the preservation, balanced use, and reinstatement of natural resources, creations and composites :  
   -  wild plants, animals and fungi;
   -  plants, animals and fungi covered by the species protection;  
   -  animals leading a migratory life;  
   -  natural habitats;  
   -  habitats endangered by extinction, rare and protected species of plants, animals and fungi;  
   -  formation of life and non-living nature and fossil remains of plants and animals;  
   -  landscape;  
   -  greenery in cities and villages;  
   -  stand density.

The aim of the conservation of nature is (art. 2, (2) of Nature Conservation Act):   
   -  maintenance of ecological processes and stability of ecosystems;  
   -  maintenance of the biological diversity;  
   -  maintenance of geological and paleonthological heritage;  
   -  maintenance of the continuity of plant, animal, and fungi species, with their habitats, by their maintenance or
      reinstatement to appropriate state of nature  
   -  preservation of landscape values, green areas, and trees in cities and villages;  
   -  maintenance or reinstatement to the appropriate state of protection of natural stands, and other resources,
      formations and natural components;  
   -  shaping proper human approach towards nature - through education, providing information, and promotion
      concerning the preservation of nature.

The National Park as a form of the preservation of nature.

Art. 8  (1) of the Act defines national park as the area distinguished by special values of a natural, educational, social, or cultural kind, covering the area not smaller than 1000 ha, where the conservation covers the whole nature and landscape values.

Art. 8  (2). National Park is created with the aim of preserving the biological diversity, resources, formations and components of inanimate nature and landscape values, reinstatement of proper condition of natural resources and components, and reinstatement of deformed natural habitats, plant, animal or fungi habitat.

Art.12 (1). The area covered by the national park is available for scientific, educational, cultural, tourist, recreational or sport activities unless they do not negatively influence the nature in the national park.

The main tasks of Bia這wie瘸 National Park, connected with the conservation of nature are as follows:
   -  protection of natural, scientific, landscape values within the Park area,
   -  identification and estimation  of the existing and potential interior and exterior threats; and undertaking appropriate
      actions eliminating or limiting the threats and their consequences,
   -  carrying out scientific researches and their initiation, making the park area accessible for research to the other scientific-researching units,
   -  manage the preservation and enclosure breeding of European bison, including the protection over the free herd of European bison within Polish part of the Bia這wie瘸 Forest area

In order to protect the variety of biocenosis and unique landscape values, within the Park area the following zoning connected with the permitted range of human interruption is applied:
   -  strict protection,
   -  active protection,
   -  landscape protection.

Strict protection means leaving the subject area under the influence of the forces of nature; and bases on no direct influence of the human being. Strict protection facilitates  ecological processes. The best example of such an action is the forest reinstatement after the stoppage of tree cutting and after the change implementation into species composition and into the structure of the forest, resulting from the natural growth of the forest stands and processes of succession. Strict protection covers the total area of 6059,27 ha (57,6 % of the Park area). That area comprises 4747,17 ha of the former BNP Strict Reserve, protecting the forest since 1921         

Active protection allows human interference, in a form of protective actions aimed at the reinstatement of the condition closest to natural ecosystems and nature components or maintenance of natural habitats , as well as plants, animal, and fungi habitats. The best example of the active protection in Bia這wie瘸 National Park is mowing and shrubs removing from meadows located in river valleys, midland meadows and areas, which remained after the old wood storehouses in  Hwo幡a Protective Unit. These are the places where many rare and valuable species of plants appear, inter alia marsh gentian, marsh pea, mat-grass, Succisella inflexa (Kluk) Beck or orchids, and rare bird species (corn crake, common snipe, lesser spotted eagle). Maintenance of an open character of these places requires the stoppage of natural succession, meaning shrubs and trees growing. Proper activities are performed in the summer time, after rare plant species finish to blossom, and when birds finish breeding. Active protection covers the total area of 4104,63 ha (39 % of the Park area).

In accordance with the Nature Conservation Act, landscape protection means the preservation of characteristic features of a certain landscape. The landscape of the Palace Park is a great advantage of Bia這wie瘸 National Park. Tree composistions and meadow systems, covering the vast areas between tree and shrub clusters, are important elements of the aforementioned landscape. In this case, landscape protection means maintenance pruning of trees and shrubs and meadows mowing/scything. In practice, very often lansdcape protection of the part of national park or nature reserve permits the economic use of the area. Such a status is usually given to private grounds within the park or reserve area, and to the technical areas (roads, car parks, buildings etc.). With a regard to Bia這wie瘸 National Park these are agricultural areas, area of the European Bison Breeding Center, the strip of the cross-border road. The Park was divided into landscape protection zones having total surface area of 353,37 ha (3,4 % of the Park area).     

The protection zone, commonly known as buffer zone, plays a very significant role in the protection of the park nature. The zone covers the surface area of 3224,26 ha. It serves the purpose of protection of the Park nature against exterior threats, with a special regard to those of an anthropogenic origin. The protection of plant, animal, and fungi species is the form of the protection of nature against the destruction or extinction of rare and valuable species.

Knowing the position of naturally valuable plant and fungi species, the number, and condition of the population of the protected animal species, we might control the threats and try to fight them in order to preserve given species.

Park personnel perform the stock-taking of the protected plant stands. Furthermore, they also take care of preservation the European bison breeding, e.g. they take care of the herd of free European bison within the Polish part of Bia這wie瘸 Forest and they monitor the herd all the time. The personnel prepares, also, the stock-counting programs referring to large predators: wolf and lynx.

Main organizational units taking care of the nature conservation in Bia這wie瘸 National Park, with the realization of statutory tasks inclusive, are as follows: 

Rezerwat Protective Unit (area of 10242,71 ha), out of which: 6059,27 ha is under strict protection, 4104,63 ha under active protection and 77,45 ha under landscape protection. The area is subdivided into six protective districts :
   -  Dziedzinka (area of 2769,97 ha),
   -  Sierganowo (area of 2303,24 ha),
   -  Cupryki (area of 1243,17 ha), 
   -  Gruszki (area of 1426,52 ha), 
   -  Masiewo (area of 1120,29 ha),  
   -  Zamosze (area of 1379,52 ha).

 
European bison Breeding Center (area of 274,56 ha). The area of the Center is under landscape protection. The area comprises the following:  
   -  three breeding reserves  
   -  European bison Show Reserve.

The duties of the personnel of European bison Breeding Center cover also the restitution breeding of European bison inhabitating all Polish part of Bia這wie瘸 Forest.