Given little research using meta-analysis for SSI-based interventions and their limitations (e.g. data selection and analysis processes), further study is needed to validate previous findings and provide a broader sense of the effectiveness of SSI-based interventions in promoting scientific literacy. Therefore, this study aimed to meta-analytically investigate the effect of SSI-based intervention studies on students' scientific literacy. Several keyword patterns were searched for various databases (e.g. ERIC, Springer Link, and Taylor & Francis) to elicit related papers. After applying inclusion and exclusion criteria, the current meta-analysis handled 32 intervention (experimental) studies (k = 33) that implemented SSI-based interventions to improve students' scientific literacy. The findings showed that the overall effect size for the random-effects model was found to be 1.018, which falls into the "large" effect. This means that SSI-based intervention studies are more effective in improving students' scientific literacy than traditional or regular instruction. The findings of moderator variables (educational level, type of intervention, and implementation duration) revealed that only implementation duration is a significant moderator to estimate the students' scientific literacy along with SSI-based intervention studies. It is recommended that future studies qualitatively examine the design and implementation procedures of SSI-based interventions with extreme values.