Abstract Objectives: The aim of this study was to evaluate the effect of STS resection in the thigh on MS and the HRQoL. Methods: Fourteen adults patients with STS in the thigh who underwent wide resection and limb preservation were evaluated. The patients were submitted to the Mini-Mental State Examination (MMSE). A hand-held dynamometer was used to measure the MS the flexors, adductors, abductors, and extensors muscles of the operated and non-operated thighs and between the dominant and non-dominant operated sides. The Musculoskeletal Tumor Society (MSTS) and Short Form Health Survey-36 (SF-36) questionnaires were applied to quantify the psychometric properties of the HRQoL. The data were submitted to statistical analysis using the Wilcoxon test (MS), and Mann-Whitney and Spearman correlation (MSTS and SF-36) (α = 0.05). Results: There was no significant difference in MS between the operated side and the non-operated side, and between the dominant and non-dominant operated side (ρ > 0.05). The MSTS presented a significant difference in the emotional acceptance for patients submitted to radiotherapy (ρ = 0.029). The SF-36 showed significant differences in the emotional aspect for patients submitted to chemotherapy (ρ = 0.027) and in the social aspect between the dominant and non-dominant operated side (ρ = 0.024). Conclusions: The HRQoL of adult patients is hampered after the treatment of STS even when MS is maintained.