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Fully developed compressible turbulent channel flow (Ma=0.8,Re=3300) is numerically simulated, and the data base of turbulence is established. The s tatistics such as density_weighted mean velocity and RMS velocity fluctuations i n semi_local coordinates agree well with those from other DNS data. High order s tatistics (skewness and flatness factors) of velocity fluctuations of compressib le turbulence are reported for the first time. Compressibility effects are also discussed. Pressure_dilatation absorbs part of the kinetic energy and makes the streaks of compressible channel flow more smooth. The scaling laws of compressible channel flow are also discussed. The conclusi ons are: (a) Scaling law is found in the center area of the channel. (b) In this area, ESS is also found. (c) When Mach number is not ve ry high, compressibility has little effect on scaling exponents.