The purpose of this study was to investigate the immediate effects of contralaterally controlled functional electrical stimulation (CCFES) on upper limb function in stroke patients. CCFES and mirror therapy (MT) exercises were conducted for 13 stroke patients at least 4 weeks post-onset. A sufficient interval of at least 24 hours was left between the two types of rehabilitation exercises. Before treatment and immediately after each training session, grip strength, Fugl-Meyer Assessment for Upper Extremity (FMA-UE) score and FMA-UE subscores for the shoulder/elbow/forearm, wrist, hand, and coordination were evaluated. Grip strength, FMA-UE and FMA-UE shoulder/elbow/forearm, wrist, and coordination did not differ significantly after CCFES and MT compared to before therapy. FMA-UE hand did not change significantly after MT compared to before therapy, but it improved significantly after CCFES (p = 0.013). CCFES for the upper extremities immediately improves hand function and may be effective in maintaining and improving patients' motivation for rehabilitation treatment.