Objective To study the effect of isokinetic strength training on upper limb motor function and activities of daily living (ADL) in stroke patients with hemiplegia. Methods From January to December, 2016, 56 stroke patients with hemiplegia were randomly di-vided into control group and observation group equally. Both groups received routine rehabilitation training, and the observation group ac-cepted hemiplegic limb flexor and extensor muscle isokinetic strength training in addition, for four weeks. They were assessed with Fugl-Meyer Assessment-upper limb (FMA-UL), modified Ashworth Scale (MAS), modified Barthel Index (MBI) and biomechanical index-es of elbow flexion and extension with Biodex System-4 before and after treatment. Results The scores of FMA and MBI improved after treatment (t>7.083, P<0.001) in both groups, and improved more in the observation group than in the control group (t>2.369, P<0.05). The peak torque, total work and average power at 60°/s and 120°/s angular velocity of both flexor and extensor improved in both groups (t>2.149, P<0.05), and those of the extensor improved more in the observation group than in the control group (t>2.027, P<0.05), except the peak torque at 60°/s angular velocity. Conclusion Isokinetic strength training can improve the motor function of upper limbs and activities of daily living in stroke patients with hemiplegia.