The invention discloses an automatic flanging machine, and belongs to the technical fields of machining equipment. The automatic flanging machine mainly comprises a clamping mechanism and a flanging mechanism, the clamping mechanism and the flanging mechanism are arranged on the worktable, the clamping mechanism comprises a transfer mechanism and a cutting mechanism, the transfer mechanism comprises an adaptive roller and a driven roller, the cutting mechanism comprises a bearing seat, a pressing table and a cutting blade, the pressing table is movably arranged above the bearing seat, and thecutting blade is movably arranged on one side of the bearing seat. The flanging mechanism comprises a bearing assembly and a flanging assembly, the bearing assembly comprises a base arranged on the flanging assembly, and the flanging assembly comprises a longitudinal feeding table, a transverse feeding table and a flanging roller set, the flanging roller set is arranged on the base, and the flanging roller set comprises a first forming roller, a second forming roller, a shaping roller and a ringing roller, and the first forming roller, the second forming roller, the shaping roller and the ringing roller are rotatably arranged on the base. According to the automatic flanging machine, a silicone hose can be automatically flanged through cold extrusion, safety is improved, and meanwhile the flanging effect is good.