The photonic band of a set of quasi_fractal photonic crystals, which have similar structure and include idealized metal, is computed by finite-differ ence time_domain method. The result shows that there are photonic band gaps in t his kinds of quasi-fractal photonic crystals. It is found that, with increasing fractal series, the width of the photonic band gap is enlarged, the frequency of the photonic band totally trends to high frequency quickly, at the same time, the photonic band is quickly hauled to line and become a energy level.