The study aimed to evaluate the effects of chemotherapy treatment on muscle strength, quality of life, fatigue, and anxiety in women with breast cancer. Nineteen women who were undergoing a chemotherapy treatment (breast cancer treatment [BCT] group, 52.2 ± 13.1 years) and 18 women without cancer (control [CNT] group, 55.8 ± 8.4 years) answered questionnaires for evaluation of fatigue (Fatigue Scale), quality of life (Short-Form Healthy Survey [SF-36] questionnaire), and anxiety (State-Trait Anxiety Inventory [IDATE]) levels. Muscle strength was also assessed by an isometric grip test and an isokinetic knee extension test. Physical limitations, social and emotional domains of quality of life were lower in the BCT group in comparison to the CNT group (p = 0.002; p = 0.003; p = 0.0003, respectively). The other domains did not differ between groups (p > 0.05). There were no differences in fatigue and anxiety levels between both the BCT and CNT groups (p > 0.05). Additionally, isometric grip strength was higher in the CNT group when compared to the BCT group (p = 0.048). However, there were no differences between the BCT and CNT groups for peak torque and total work at both 60°.s−1 (p = 0.95 and p = 0.61, respectively) and 180°.s−1 (p = 0.94 and p = 0.72, respectively). These results suggest that three cycles of chemotherapy treatment may impair handgrip isometric strength and quality of life in women with breast cancer.