Using XPS， AES etc. e1ectron spectroscopic techniques and TG， XRD etc. physical methods，surface properties of continuous SiC fibre made from polycarbosilicane precursors have been investigated. The effects of various pretreatment conditions on surface composition，construction and characters of the fibre have also been compared. The data show that the coating layer on the surface of SiC fibre can be removed by heat-treatment at the temperature of 500℃ or by macerating with acetone，bulk construction in the SiC fibre may be ultra-fine crystallite of β-SiC; on its surface there is a layer of silicon oxide，which may be a-SiO₂ crystallite. When calcined. at 500℃ in the air，the layer of silicon oxide on the surface of the SiC fibre thickens and the free carbon content in the surface decreases with the calcinating time. This kind of silicon oxide in the surface layer of the SiC fibre has good stability in acids but is likely to dissolve in the hot concentrated alkalis.