A warming oven includes a base, a heating unit, a heat conducting unit, and a reflective shield. The base has an accommodating space. The heating unit is disposed within the accommodating space. The heat conducting unit includes a positioning plate, a top plate spaced apart from the positioning plate, a quartz glass tube inserted into the positioning plate and the top plate, and a plurality of upright connecting rods disposed around the positioning plate and the top plate. The reflective shield is formed with a plurality of vent holes, and includes a bottom cover that covers a top end of the heat conducting unit and that has a vertically curved outer mirror surface for reflecting light from a fire flame produced by the heating unit, thereby providing an illumination effect.