Formation,structure and magnetic properties of Ho2Fe17Cx compounds prepared by melt-spinning were studied. These carbides are found to be stable at high temperature. Their crystal structure changes from the hexagonal Th2Zn17-type to rhombohedral Th2Zn17-type,as x increases. Saturation magnetization of Ho2Fe17Cx compounds at 1. 5 and 300K were measured, and no dependence of Fe magnetic moment on carbon concentration was found. The introduction of carbon atoms results in the expansion of unit cell volumes and the rising of Curie temperature. According to the molecular field model,we suggest that the rising of Curie temperature with x is mainly due to the enhancement of Fe-Fe exchange interactions by introduction of interstitial carbon atoms.