The bridging effect of steel fiber and its synergistic effect with rubber particles can significantly improve the performance of concrete, but there are few studies on the static mechanical properties and constitutive relationship of self-compacting concrete mixed with steel fiber and rubber. To prepare self-compacting concrete specimens with steel fiber and rubber, the rubber concrete with 10%, 20%, and 30% rubber powder content were mixed with the steel fiber content of 0.5%, 1.0%, 1.5%, respectively. Prismatic axial compression tests were carried out to investigate the effects of steel fiber content and rubber powder content on the typical mechanical characteristics of specimens and the constitutive relationship of the axial compressive strength of the self-compacting concrete mixed with steel fiber and rubber was put forward. The results show that the failure of self-compacting concrete specimen mixed with steel fiber and rubber presents ductile failure, while its integrity is good. With the increase of rubber powder content, the axial compressive strength of the specimen gradually decreases. When the rubber powder content is high (20%, 30%), steel fiber has no obvious enhancement effect on the axial compressive strength of self-compacting concrete with rubber. The addition of rubber powder increases the peak strain of the specimen. The peak strain of the specimen reaches the maximum (an increase of 10%) when the amount of rubber powder is 10%. Different amounts of steel fiber can generally enhance the peak strain of self-compacting concrete mixed with steel fiber and rubber, but it does not show obvious regularity. The axial compressive constitutive relationship can reflect the mechanical properties of self-compacting concrete mixed with steel fiber and rubber powder.