Human intensive activities have caused a number of changes in nature, including biodiversity deterioration and the decline of pollinator numbers, which consequently lead to problems in agricultural production and also cause economic losses. The production of cultures whose yield largely depends on the pollination of insects, such as watermelon, becomes increasingly demanding. The aim of the research was to determine the number and types of pollinators on flower belts integrated in the watermelon field, to compare the number of pollinators present on floral belts with the number of pollinators present in the natural agro-soil and to determine the influence of the pollinators on the watermelon yield. The floral belt was located at the Tovarnik site. Inside the floral belt and the part of the crop without the floral belt, three areas of 3x3m were determined and were photographed. An estimate of the flowering for families Fabaceae, Apiaceae, Asteraceae, Brassicaceae, Lamiaceae, and other sown and wild flowers was recorded. The percentage of flowers within the mentioned groups was recorded according to the given scale. Four groups of pollinators (on the part of the crop with the floral belt and on the part of the crop without the floral belt) were monitored as follows: inside the floral belt a strip of > 50 m length was chosen, then the surface of 3x3 m was observed for 4 minutes without change of position. The number of present fauna was recorded in three repetitions. Reading was done twice a month in the period from June to August. During the sampling of 4 plants in 4 replicates in the first 4 rows on the part of the crop with and without the flower belt the number and weight of the fruit of the watermelon per plant were recorded. There is a higher average number and a higher average mass of watermelon per plant on the part of the crop with the floral belt compared to the part of the crop without floral belt. Flower belts have a positive effect on the diversity of pollinators and on the yield of watermelons and are therefore considered as good agro-environmental measures.