Time synchronization is one of the important aspects in wireless sensor networks. Time synchronization assures that all the sensor nodes in wireless sensor network have the same clock time. There are various applications such as seismic study, military applications, pollution monitoring where sensor nodes require synchronized time. Time synchronization is mandatory for many wireless sensor networks protocols such as MAC protocols and also important for TDMA scheduling for proper duty cycle coordination. Time synchronization is a stimulating problem in wireless sensor networks because each node has its own local clock which keeps on varying due to variation in the oscillator frequency. The oscillator frequency is time varying due to ambient conditions which leads to re-synchronization of nodes time and again. This re-synchronization process is energy consuming whereas energy is constraints in WSN. This paper proposes a novel cluster based time synchronization technique for wireless sensor networks in which cluster head rotation is based on minimum clock offset. Simulation results based on energy analysis of the proposed model demonstrate that proposed novel cluster based time synchronization technique reduces the energy consumption and also the synchronization error compared with other existing protocols.