In the economic life of the region, agriculture is of paramount importance. 71% of the population is connected with it. 29,4% of the region's population depends on agriculture exclusively for their living. Individual farmers own 99,3% of the whole arable land. An average farm coverse an asce of about 10,5 ha. A decrease in the number of farms in favour of the increase in their area has been observed recently (12341 farms at present).
Arable grounds predominate in this area, out of which the majority are of the 5th and 6th class (70%) . The quality of soit determine,the direction of farming, in which corn-growing (58%) and potatoes (15%) are prevailing, especially in the southern part of the county, i.e. in Goworowo, Czerwin, Troszyn and Rzekuń. Beside vegetables, fruit and sugar beets which are also grown here, cattle- breeding is significant. It provides material for the local meat processing factories, among which the Meat Factory JBB in Łyse adjusted to the European standards.
The main direction in the animal production is milk cattle-breeding which isdetrmined by large propartion (50%) of the grassland in the total amount of arable land. The majority of meadows and pasture land is located in the northern part of the county. For example, in the Baranowo district they constitute 69,6% of arable land, in districts Myszyniec - 62,3%, Lelis - 58,7%, Kadzidło - 55,8% and Łyse - 55,7%. It is worth mentioning that the county of Ostrołęka has the biggest number of cattle per 100ha of arable land and the highest milk production in the Mazowieckie Province.

The development of the county is closely connected with milk production. There is an increasing demand for high quality milk which has been used by the leading milk processing factories in Poland for a long time. Milk processing industry is exceedingly attractive for foreign investors. Hochland company (with German capital) building a modern factory in Baranowo may serve as a good example. Hochland is planning to co-operate with the already existing Spółdzielnia Mleczarska 'Kurpie' (dairy industry). It proves that the materials produced here are of an exceptionaly high quality which is mainly a result of the minimal use of artificial fertilisers and pesticides in clean natural environment. Intensive animal production, however, may put the natural environment in danger. Following the old saying 'prevention is better than cure' the National Fund for the Environment and Water Resources Protection with a support of the World Bank, included these regions within the programme ' Environment protection in the countryside'. The programme focuses on training as well as on investments. Farmers' task is to adjust their production to the European Union's requirements. In order to expedite this process, another programme called 'The preparation of milk producers for the standards of the European Union' financed by the Project of the Pro-European Initiative PHARE '97 European Integration, has been launched. The development of infrastructure is becoming a priority in Polish villages. Rapid improvement of water supply for village population is registered every year. Advanced works are being conducted as far as providing the sewage system is concerned. The condition of roads is gradually improving. Gas supply and telephone services are also advancing. Looking for alternative income sources is still an essential incentive of the county's agriculture. The hitherto existing production is being replaced with the production of mushrooms, herbs and flowers, small handicraft, especially the production of folk artefacts and, finally, agriturism. All this is facilitated by the region's precious nature, good condition of the environment and favourable location near Warsaw.