The study aimed to investigate the factorial invariance of mathematics and science attitudes scales for eighth-grade students in the TIMSS 2019 International Study in the Omani context, across gender (male, female). The descriptive analytical methodology was used to analyze the responses of the study sample on the two scales, with a total sample size of 6,738 students. The scales consisted of 34 and 33 items distributed across four dimensions for mathematics and science attitudes, respectively. Confirmatory factor analysis and multi-group confirmatory factor analysis were employed to assess the fit of the theoretical model for each scale and examine the level of factorial invariance across gender using the R statistical analysis software. The results revealed a lack of fit for the assumed theoretical model and demonstrated an accepted fit for the modified models in both scales. Additionally, the results indicated the residual invariance for the mathematics attitudes scale and scalar invariance for the science attitudes scale. Furthermore, the study addressed gender differences in attitudes towards mathematics and science. The results indicated an increase in male preference for science compared to females, while differences between males and females were distributed across dimensions of the mathematics attitudes scale