It is well known that supplementation with high protein after exercise can effectively promote muscle synthesis and repair, while green tea is rich in catechins that have antioxidant effects. We aimed to explore the effects of green tea combined with isolated soy protein on increase muscle mass in resistance-trained mice. A total of 32 male ICR mice (8-weeks old) were divided into four groups ( = 8/group), sedentary control group (SC), isolated soy protein with green tea group (ISPG), resistance training group (RT), isolated soy protein and green tea combine with resistance training group (ISPG + RT). All mice received control or ISPG by oral gavage for four consecutive weeks. Forelimb grip and exhaustive swimming time were used for exercise performance evaluation. In biochemical profile, we analyzed lactate, ammonia, blood urea nitrogen (BUN), and glucose and muscle damage index creatine kinase (CK) after exercise as biochemical parameters of exercise fatigue. The grip strength, muscular endurance, and exhaustive swimming time of the ISPG + RT group were significantly increased than other groups ( < 0.05), and also significantly decreased in serum lactate and ammonia levels ( < 0.05, respectively). The ISP + RT group was not only increased in quadriceps weight, ( < 0.05) but also decreased EFP ( < 0.05). We recommend using a 4-week supplementation with ISPG, combined with RT, to increase muscle mass, exercise performance, glycogen storage, and reduce fatigue biochemical parameters after exercise. The benefits of long-term supplementation or application to human supplementation can be further explored in the future.