The utility model relates to a compression and pull-out variable diameter reinforcement cage belled pile, which consists of an enlarged head pile bottom of a variable diameter reinforcement cage skeleton, a pile body connected with a fixed pile bottom, and the diameter of the pile body is lower than that of the enlarged head pile bottom When the variable diameter reinforcement cage at the pile bottom is connected with the reinforcement cage or steel pile of the traditional cast-in-place pile, the connection mode between the pile body and the reinforcement or steel pile of the variable diameter reinforcement cage at the bottom of the enlarged head pile is riveting, pin, welding and flange It can give full play to the horizontal load bearing performance of each pile, and the end and bottom are expanded, which is conducive to the grouting expansion at the pile bottom; The enlarged pile bottom (head) has stable behavior and large load cutting force The invention is especially used for the structure with pile bottom as cast-in-place pile: rotary excavation pile, bored cast-in-place pile, immersed pipe cast-in-place pile, manual hole digging cast-in-place pile, explosion expansion cast-in-place pile, etc