Unmanned Aerial Vehicles (UAVs) have become the necessary tools for a wide range of activities including but not limited to real-time monitoring, surveillance, border patrolling, search and rescue, civilian, scientific and military missions, etc. Their advantage is unprecedented and irreplaceable especially in environments dangerous to humans, for example in radiation or pollution exposed areas. A method for occlusion-aware UAV path planning is presented in this paper, which ensures every point on the target ground area can be seen at least once in a complete surveillance circle. Besides, the geometrically complex environments with occlusions are considered in our research. Compared with many existing methods, we decompose this problem into a waypoint determination problem and an instance of the traveling salesman problem.