This study aims to investigate the comparison of metallurgical and mechanical properties of laser and laser-GMA-hybrid welded joints of high strength low alloy (HSLA) of SA516 grade 70 steel of 4 mm thick plate. The welding was performed using Nd: YAG laser under continuous wave mode. Various studies like micrograph, SEM/EDS analysis, micro-hardness, tensile test, impact test and fractographic were carried out to investigate the structural-property relationship between the weldments. Microstructure of the fusion zone during the laser welding process shown the presence of bainite and martensite phases. Meanwhile, the fusion zone of laser-GMA-hybrid weldment was predominant with the acicular ferrite. The average micro-hardness of laser weldment, at the fusion zone was nearly 40% more than that of Laser-GMA-hybrid weldment fusion zone. SEM/EDS analysis for the laser-GMA-hybrid weldment contains 7.66 wt% of oxygen at the fusion zone. The tensile test results revealed that fracture occurred well above the HAZ for the both laser and laser-GMA-hybrid weldment. © 2017 Elsevier Ltd. All rights reserved.