Wireless sensor networks (WSNs) have been considered as a promising method for reliably monitoring both civil and military environments under hazardous or dangerous conditions. Depending on different applications, data transmission in the WSNs maybe mixed with the demands for reliability awareness, energy efficiency and time sensitivity. Therefore, Reliable data transmission with the lowest energy consumption and time delay is an important issue in current research. In this paper, we propose a reliable data transmission protocol over multi-path in the WSNs. It does not only provide the desired reliability for data transmission, but also minimize the energy consumption and time delay while transmitting. The simulation results and analysis show that our Low Cost Reliable data Transmission over multipath (LCRT) protocol can provide reliable data transmission and achieve much better performance on transmission time delay and energy consumption.