The present investigation was carried out in Assiut region during blooming period (August, 2005) to evaluate the role of insect pollinators on sunflower.  The effects of nearness of the fields to honey bee colonies and the weather conditions on pollinators, activity during blooming period as well as the impacts of these factors on seed setting and yield of sunflower crop were also studied.  The results showed that the highest activity of insect pollinators especially honey bee was noticed at 10:00 a.m.   Honey bee comprised about 96% of all pollinators of sunflower.  There was a significant difference in the average numbers of honey bee individuals between the two distances, 500 and 1000 m away from the bee colonies.  The bee numbers decreased to one-half with increasing the distance by two-folds.  Positive correlations were found between honey bee activity and each of maximum, minimum and average daily temperature. Negative correla-tions were found between the bee activity and each of maximum, minimum and average relative humi-dity, and wind velocity. The coeffic-ient of determination was 0.79, indicating that the daily temperature, relative humidity and wind velocity accounted for 79% of bees activity changes.  Bee pollination increased seed number by 81% and 71% for near and faraway field, respectively.  The setting of seeds was significantly higher (96.9%) in the near field than in the faraway field (86.8%).  The incre-ment in seed weight of unbagged heads was about 365% and 340% for near and faraway fields, respectively as compared to bagged heads