Purpose: The purpose of this study was to develop and evaluate the effects of a support group intervention on the burden of primary family caregivers of stroke patients. Method: A nonequivalent control group pretest-posttest design was used. The subjects were 36 primary family caregivers of stroke patients [experimental(N=18) and control(N=18) groups] in a neurosurgery ward of a university hospital. The experimental group members participated in six sessions of a support group intervention for two weeks and the degree of their caregiving burden was evaluated. Data was analyzed by Chi-square tests, t-tests, and paired t-tests using SPSS 10.0. Result: The experimental group had a significantly lower total burden score (t=2.06l, p= .047)and sub-scales of emotional(t=-3.319, p= .002), time-dependent(t=-2.045, p= .049) and developmental(t=-2.656, p= .012) burden scores than the control group, while no significant differences were found in physical, social or financial burden scores between the two groups. Within the experimental group, there was a significant decrease in physical(t=2.507, p= .023), emotional(t=4.754, p= .000), social(t=2.932, p= .009), time- dependent(t=5.015, p= .000) and developmental(t=7.541, p= .000) burden scores but not the financial burden score. Conclusion: The results suggest that a support group intervention can be utilized as an effective nursing program to reduce the burden of primary family caregivers of stroke patients.