In recent years power control becomes one of research hotspots in wireless sensor networks to reduce total energy consumption in packet interference and improve channel spatial reuse. For the random power control approach, the wireless module of a sensor node picks up one stochastic power value between the minimum and the maximum to send data packet. Connectivity of the random power control approach in wireless sensor networks where sensor nodes are distributed densely is analyzed in this paper. The minimum and the maximum can be selected to meet the performance requirement of networks. Simulation results show that random power control can improve the energy efficiency compared to the conventional fixed power control under the tiny difference of transmission successful probability.