With the advantages of "small, fast and flexible", unmanned aerial vehicle were gradually used in urban logistics distribution. The UAV delivery model was first described in this paper, including locomotive cooperative mode and UAV independent operation mode. Secondly, the influencing factors of UAV delivery path planning were described, including energy consumption, restricted area obstacles and other factors of flying around and uncertain natural environment. Finally, according to the two delivery modes, the influence of internal and external factors on UAV delivery path planning were discussed. The results show that the non-linear UAV energy consumption model is more consistent with the actual operation characteristics of UAV. Weather factors such as wind and temperature affect the flight direction and power consumption of urban distribution of UAVs. No-fly zones, time Windows and other external factors also affect the path planning of UAVs. In actual operation, the UAV is affected by multiple factors. The research on the influence of energy consumption and external factors on path planning of UAV needs to be further improved.