This study was conducted at Faculty of Agriculture, South Valley University, Qena Government, Egypt during the seasons 2011, between two hybrid of the Carniolian bee race and second hybrid of the Italian bee race to study the relationship between the infection levels of Nosema apis spores and epithelial cells of midgut of honeybee.
          The results showed that there were high significant differences between the average numbers of spores; where the numbers of spores in Carniolian bee race higher than the Italian bee race (20467.26-11402.03), respectively during the study period. On the other hand histological section showed that heavy infection lead to the disintegration of epithelial cell walls, striated border, and fragmentation of peritrophic membranes. Also, destruction of the muscle layer and basement membrane, while in the case of moderate cells infection appeared semi-decomposed compared to healthy cells. The research recommends to intensify the care and treatment programs during months of heavy infection (January, February, March), in the southern states.