The pulsed laser deposition (PLD) technique can be efficient and cost-effective in the fabrication of high-quality MoS2 thin films. The laser pulse parameters, such as the number of pulses, the pulse energy density, and the frequency, that influence the MoS2 thin films quality have been investigated. The optimum parameters of laser pulse for the best crystalline quality MoS2 films were determined by experiments. Back-gated field effect transistors (FETs) were fabricated based on the MoS2 thin film. The carrier mobility of the MoS2 back-gated FETs has reached 4.63 cm2 V−1 S−1. The responsivity of the MoS2 back-gated FETs is approximately 0.06 AW−1 at drain voltage of − 2 V. These results show that the back-gated FETs based on MoS2 thin films prepared by PLD can be applied to photodetectors.