Today, the wireless sensor networks are popular therefore they have high features such as small tools, high computational ability and usability in all environments. But restriction power is the weakness that clustering is trying to improve. Clustering usually pays attention to two imensional WSNs. In this paper, three-dimensional geometric forms have been focused for some places in which reviewing different environments with different surfaces is necessary. Based on a mathematical model for the presented 3D clustering method we calculate the network life time according to the number of used sensors.