Cutter fixing device convenient to replace and used for lathe machining

The utility model discloses a lathe machining cutter fixing device convenient to replace, and relates to the technical field of lathe machining, the lathe machining cutter fixing device comprises a fixing seat and a cutter holder, and a connecting mechanism is arranged between the fixing seat and the cutter holder; the connecting mechanism comprises a first connecting base, a first moving base, a second moving base, a second fixing block and a clamping block. By arranging the connecting mechanism, the tool apron can be conveniently and rapidly replaced, loosening of a tool caused by vibration is not prone to occurring, the clamping block and the first moving seat are kept in a clamped state, and therefore the situation that the threaded rotating rod and the first moving seat are loosened, the first fixing block moves out of the interior of the tool apron, and the first moving seat relieves extrusion on the second moving seat is avoided; the second fixing block moves along the inner wall of the second connecti