Purpose: This study aims to evaluate student motivation before and after the summer internship, in other words, to evaluate whether the summer internship affects male and female motivations differently. Design/methodology/approach: Investigating whether the motivation score predicts grade point average was included by adopting a quantitative methodology. The defense engineering summer internship project provides candidates who learned defense engineering knowledge after the project an opportunity to generate motivation of involving in defense engineering discipline and industry. Findings: This study found a marginal significant main effect on extrinsic motivation -- introjected (EMIN) and intrinsic motivation to experience stimulation (IMS) in a summer internship. Furthermore, the study reveals that amotivation construct significantly predicted gender and previous academic performance (GPA) pre-summer internship, and amotivation, Extrinsic motivation -- external regulation (EME) and extrinsic motivation -- introjection (EMIN) significantly predicted GPA post-summer internship. Originality/value: These findings are investigated from the project.