Abstract: A fairly comprehensive study was made on the physical and mechanical pro-erties of acety-lated and untreated bamboo (Phyllostachys pubescens) samples, which indicated that though bamboo samples No.2 and No.3 were the same in shape and size and went thorough the same acetylated treatment, the weight gain percentage (WPG) of the samples might be different. The WPG of sample No.2 was lower than that of No.3, with the former being 19.28%?.98 and latter 22.66% + 1.69. As the cacu lated value of significance (T) was over 2, the differences between the two were apparent.After acetylation, the bamboo samples gained in density and basic density, while their shrinkage, volumetric shrinkage and wet swelling reduced.During acetylation, the bamboo samples lost, to certain extant, their mechanical strength. Before the treatment, the mean value of compressive strength of sample No.2 was 702.07?0.2kg/cm2, and that of No.3 was 664.81 + 16.87kg/cm2, while the value of sample No-2 was 664.93?82kg/cm2 and No-3 615.10?9.8lkg/cm2 after the treatment.