The study was conducted to evaluate efficiency of artificial insemination (AI) service and constraints of AI service selected Districts of Harar National Region State, Ethiopia. A total of 320 dairy cows were randomly selected from six districts of Harari region; Jin'Eala, Shenkor, Hakim, Dire-Teyara, Aboker, Sofi. Data on dairy cattle management, artificial insemination (AI) service. Sperm needs some time in a cow's reproductive tract before it is capable of fertilising an egg. Therefore, Artificial insemination should take place in the last two-thirds of heat or a few hours after heat has finished, representing a window of just 12-18 hours from when an animal first comes on heat. Semen handling in beef cattle breeding.