This article describes the synthesis of molybdenum disulfide (MoS2) nanowires using chemical vapor deposition (CVD) method. The MoS2-nanowires converts into micro-flake structures with the help of argon (Ar) plasma for the better hydrogen evolution reaction (HER) activity. The MoS2-nanowires treated by post-Ar plasma at different time of intervals (20 seconds, 40 seconds, 60 seconds, and 3 minutes). The plasma treatment significantly tailored the structure of pristine MoS2-nanowires due to which additional active sites were produced at the surface of treated MoS2. A notable HER activity were achieved by plasma-treated MoS2. To boost the HER activity up to next level, visible light was used at the time of electrocatalysis which enhanced the electrocatalytic activity almost double, which is evident by the low overpotential (190 mV) at current density of 10 mAcm(-2).