Indoor positioning in wireless local area network (WLAN) has been attracting increasing attentions for its cost effectiveness and reasonable positioning accuracy. Existing positioning methods all pay attention to establish more accurate relationship between received signal strength (RSS) and physical locations. However, the deployment of access points (APs) is ignored. This paper proposes an optimized APs deployment method for improving WLAN positioning accuracy. The objective of APs deployment is to maximize the RSS Euclidean distance between physical locations. We investigate and demonstrate the importance of RSS Euclidean distance to WLAN positioning. Simulation studies and experimental results show that the proposed APs deployment method can improve positioning accuracy significantly.