A three-dimensional (3D) modeling method of clothing considering background factors includes determining a first observation direction in which the clothing is to be observed based on a user input in a first space that is a background of a clothing display; determining a display shape of the clothing according to the first observation direction; determining a display shape of the first space according to the first observation direction; when overlapping and displaying the display shape of the clothing on the display shape of the first space, extracting a fusion part requiring a fusion of the display shape of the first space and the display shape of the clothing on the display shape of the clothing and determining a shape of the extracted fusion part; and overlapping and displaying the display shape of the clothing on the display shape of the first space, comprising the fusion part.