A sill-free door structure mainly comprises a door frame, a door leaf and a doorsill, wherein the door frame is composed of an upper frame strip, a left frame strip and a right frame strip, the door leaf is composed of a door leaf body, glass and a pressing line, the door leaf body is composed of an upper door leaf material, a lower door leaf material, a left door leaf material and a right door leaf material, the doorsill is mainly composed of a pre-buried heightening material part and a footboard part, the pre-buried heightening part material is installed under a decorating floor finish, is of a multi-cavity structure, and is made of nonmetal materials, and one of the cavities is internally provided with a load-bearing profile; the footboard part of the doorstill is made of aluminum alloy material, is installed above the decorated surface, and adopts a broken bridge form or a non-broken bridge form; the upper frame strip and the left frame strip forms an angle with 45 degrees, and the upper frame strip and the right frame strip also form an angel with 45 degrees; the left frame strip and the doorstill at the lower part form a structure with 90 degrees, and the right frame strip and the doorstill at the lower part also form a structure with 90 degrees, and the doorsill is transversely arranged in full length; the frame strips are composed of aluminum alloy profiles at the outdoor side, alloy and resin profiles in the middle and wood coating materials at the indoor side; the sill-free door structure has the characteristics that the structure is simple, the usage is convenient and reliable, the airtightness and the aesthetics are guaranteed, and the energy-saving requirement is met, and the like.