38% of all upper extremity injuries that patients arrive in emergency rooms are fingertip injuries, according to statistics. When the extensor tendon on the dorsal surface of the hand's distal phalanges is injured, one of the most common injuries the mallet finger occurs. It is common to sustain a mallet finger. This case report's objective is to provide a summary of the mallet injury and potential side effects. Complications must be identified, diagnosed and managed promptly to be avoided. The Symptoms, diagnosis and treatment of mallet finger injuries are all briefly covered in this case report. This case study demonstrates the critical function of physiotherapy in the recovery of a mallet finger patient by improving strength, ROM and ADL. Physical exercise and a rehabilitation protocol significantly improved outcome measure. Conclusion: During the DIPJ immobilization period, range-of-motion exercises for proximal joints and unaffected joints were useful. Ultrasound, Active range of motion exercises, grip strengthening exercises and Home exercise programs and Supplemental interventions may include counselling and informational sessions on the condition. According to our study, Physiotherapy treatment can improve the condition and increase the range of the DIPJ.