The current study investigated the effect of various artificialdiets, as pollen substitues, on the blood cells in worker larvae of honeybee. Honeybee colonies were provisioned with four pollen substitutes. Samples of blood were pulled from worker larvae and distributed directly onto glass and examined with 1250x microscope. At most, the prohaemocytes, plasmatocytes and oenocytes recorded the higher numbers in larvae collected from colonies that fed with pollen substitutes than those did not feed (control). But, the coagulescytes with/without granules and spherulescytes recorded lower numbers in larvae collected from colonies that supplied with pollen substitutes than those did not supply (control). the highest amount of prohaemocytes cells in larvae fed with pollen substitutes (diet A, B, D) was accounted for buckfast hybrid followed by the Italian and Craniolan hybrids after one day from feeding. In respect to diet "C", the highest number of prohaemocytes cells was recorded for Craniolan followed by Italian and buckfast after one day from feeding. In all hybrids, the prohaemocytes cells were more in worker larvae fed with pollen substitutes than those did not.