This paper aims to research about how to control the vigorous bamboo forest expansion, through surveying the cleared Japanese cypress forest stands which were seriously invaded by Phyllostanchys pubescens and P. bambusoides. After clear cutting in April to June, both bamboo species soon sprouted temporal bamboo grass-like shoots, without near the stand of remaining bamboo forest. In the next spring of normal shooting season, in the stand near the remaining bamboo forest, the similar size of bamboo shoots sprouted vigorously, and in the bamboo grass-like stand, the bigger shoots by 3 or 4m height sprouted a lot. On the other hand, after clear cutting, vigorous woody pioneer plants such as Fagara ailanthoides and Mallotus japonicus also grew thick in every stands. However, as the sprouted bamboo shoots were not suffered any damage by the pioneer plants, it is considered to be necessary to cut again the sprouting bamboo shoots for controlling their expansion.