Abstract Background Enhancing the sense of work gain serves as a crucial approach to invigorating S&T innovators. However, there is currently a lack of specialised instruments for measuring S&T innovators' sense of work gain (STISWG), thus limiting the progress of empirical research in this field. Consequently, this study aims to develop and validate the STISWG scale based on the Existence, Relatedness and Growth theory to address this issue. Methods The development and validation of the STISWG scale spanned four stages and cumulatively used valid questionnaire data from 1,597 S&T innovators. The analysis methods encompassed item analysis, exploratory factor analysis (EFA), confirmatory factor analysis (CFA), reliability analysis, and assessment of the external predictive validity by using the Employee Innovative Behaviour Scale and the Paternalistic Leadership Scale. Results The STISWG scale and three subscales had satisfactory reliability across all stages. EFA indicated that the 11-item STISWG scale comprised three dimensions: existence gain, relatedness gain and growth gain. CFA confirmed that the three-factor structure of the STISWG scale was the most optimal. The results of the predictive validity revealed that all three dimensions of the STISWG were good predictors of innovative behaviour. Three dimensions of paternalistic leadership moderated the above relationships, with authoritarian leadership weakening them and benevolent and moral leadership strengthening them. Conclusions This study provides an effective and specialised instrument for assessing S&T innovators' sense of work gain. Moreover, it offers practical implications for enhancing the sense of work gain and innovative behaviours of S&T innovators.