In this study, a solution-processed synthesis method was developed and successfully synthesized large-scale and uniform MoS2 thin films without using chemical vapor deposition. The MoS2 precursor solution was formulated by a sulfur-dissolving method to obtain uniform coating properties. MoS2 thin film was prepared by simple spin-coating and a one-step annealing method. The solution-synthesized MoS2 thin films were characterized to examine the 2H MoS2 structure. The various atomic layers could be controlled with the precursor concentrations. For example, two layers were obtained with 0.0070 M, three layers were obtained with 0.0125 M, and five layers were obtained with 0.025 M of MoS2 in the precursor solution, which were confirmed by scanning transmission electron microscopy.