Objective:To observe the tendency of VSN (visual spatial neglect) patients' performance after the application of low frequency rTMS and explore if series of consecutive rTMS induce cumulative effect and if the cumulative effect is the important mechanism of the therapeutic method. Method: Twelve VSN patients were divided into treated group and controlled group. The prior group was treated with low-frequency rTMS for ten days and they were asked to perform the line cancellation and line bisection tests every two days. Result: The magnitude of the effect increased with increasing number of rTMS daily sessions. Significant correlations were found between the magnitude of the effect and the number of rTMS sessions. In the treatment group, r=-0.659 and -0.606 for cancellation and bisection test, respectively. There were no correlations between the evaluation results and the increasing time in the controlled group. P=0.531and 0.167 for cancellation test and bisection test, respectively. Conclusion: Consecutive rTMS induces a cumulative effect and the effect plays a key role in the improvement of VSN symptom.