Introduction: Basketball is a sport of skillful competition. It demands characteristics from its athletes such as agility, balance, and a confrontational spirit. This requires a great improvement in strength, speed, endurance, and physical conditioning. Objective: Study the effects of eccentric muscle strength training in the lower limbs on balance ability in basketball players. Methods: Current scientific literature was used to design an experimental method with statistical data analysis. The research subjects were divided into 4 groups for a 6-week eccentric training intervention, and the effect of eccentric exercise on flexibility and balance in basketball players was investigated. Results: Compared to the pre-test and after the training intervention in the test group, there was a very significant difference (P<0.01); only the intervention group showed a significant difference (P<0.05). Conclusion: Eccentric training at the end of basketball training has a positive effect on improving flexibility and balance in basketball players. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.