A blade holder assembly for blender having a cup body arranged on a cup base; the cup base connects the cup body and a blade holder component; the blade holder component has a blade holder below and connected with the cup base; a handle is arranged on the bottom of the blade holder; connecting members are arranged on both ends of the handle; a locator is on the bottom of the blade holder; a connector is arranged at the center of the locator; a guide bone is on the edge of the blade holder, and a rotary button is in the guide bone; on the rotary fastener, two fastening members are arranged; the connecting members are connected with the rotary fastener; a guide slot is on the inner edge of the cup base; in the guide slot, a convex button is arranged for fastening the rotary fastener.