Purpose This study is aimed at determining the impact of work-related low back pain (LBP) on functional performance and physical capabilities. Methods This cross-sectional study included women (n = 25, mean age, 38.12 ± 4.59) and men (n = 25, mean age, 37.20 ± 5.38) with a history of work-related mechanical chronic LBP who visited our university hospital's outpatient department. All participants were assessed for primary outcomes, including the severity of LBP on rest and on activity, functional performance, and physical capabilities using a numeric pain rating scale (NPRS), Roland-Morris disability questionnaire (RDQ), five-time sit-to-stand test (FTSST), and fifty-foot walk test (FFWT), respectively. Independent t-tests compared the scores of the outcomes between groups while Pearson's correlation coefficient identified the correlation between the outcomes' measures at a significance level of 0.05. Results With a response rate of 63.29%, a total of fifty participant's data were obtained for the analysis. A comparison between women and men groups highlighted a significant difference in the scores of the FTSST and FFWT; however, there were insignificant differences in the scores of the NPRS at rest, NPRS on activity, and RDQ. The bivariate correlation revealed a highly significant, positive, and moderate correlation between the scores of NPRS at rest and FTSST, NPRS on activity and FTSST, NPRS at rest and FFWT, NPRS on activity and FFWT, FTSST and RDQ, and FFWT and RDQ in the women group. Similarly, there was a significant, positive, and low correlation between the scores of FTSST and RDQ and FFWT and RDQ in the men group. Conclusion Work-related chronic LBP affected the physical capabilities of women more than those of men. However, it equally affected the functional performance of all participants in the study. Furthermore, work-related chronic LBP affected the physical capabilities (FTSST and FFWT) and functional performance (RDQ) of women more than those of men.