The invention discloses an automatic clamp ring installation mechanism which comprises a bracket, a first cylinder, a gripping device, a guide bearing device, and a pushing-in device, wherein the first cylinder, the gripping device and the guide bearing device are fixedly on the bracket; the pushing-in device is driven by the first cylinder to move up and down; the guide bearing device comprises a fifth cylinder, a third clamping jaw driven by the fifth cylinder to take opening and closing actions, and a guide jig clamped by the third clamping jaw; and from top to bottom, the guide jig comprises a clamping part, a guide part and a hollow cone part with a plurality of gaps formed in the surface. According to the automatic clamp ring installation mechanism disclosed by the invention, the cone part with the gaps in the surface is arranged in the guide jig, and thus, on one hand, by utilizing the characteristic that the diameter of the cone part is gradually increased from top to bottom, a clamp ring can be supported and prevented from falling off so as to achieve bearing on the clamp ring; and on the other hand, by utilizing the condition that the cone part can shrink inwards, the cone part is matched with a second clamping jaw to push the clamp ring sleeving the cone part into a product to be installed, so that the defects of difficulty in gripping due to a small size of the clamp ring and difficulty in installation due to a narrow and small installation space are overcome.