In the present study, a total of 224 camels infested with Hyalomma dromedarii ticks were investigated for the presence of Theileria camelensis infection in Upper Egypt. The role of Hyalomma dromedarii ticks as the vector of this parasite was also investigated by haemolymph smear examination. Results revealed that 15 (6.75%) of 224 camels were harboring Theileria camelensis in erythrocytes. Furthermore, the theilerial schizont was also seen in lymphocytes. These 15 camels did not show any abnormal clinical signs except three cases that showed enlargement of superficial lymph node and fever. Examination of ticks showed various developmental stages of different shapes and forms of Theileria species.