Abstract: A knockdown hand tool structure. The structure includes a grip, a screwdriver stem, a fitting post and a socket. A front end of an elongated stem of the grip is formed with a central hexagonal fitting hole with a certain depth. A stop sleeve is fitted on the front end of the elongated stem. A steel ball and a compression spring are received in the stop sleeve. The screwdriver stem is a hexagonal stem body. Two ends of the screwdriver stem are respectively equipped with different specifications or patterns of screwdriver heads. Certain portions of the body of the screwdriver stem are formed with annular engaging grooves with V-shaped cross-section and a certain depth at equal intervals. The fitting post is a short cylindrical body.