The present invention relates to a rail and a door roller of a window and door system and a window operation apparatus for windows and doors using the same. The rail and the door roller of a window and door system and the window operation apparatus for windows and doors using the same according to the present invention include: one or more upper linear rail units 1 which are installed on an upper end of a window casing, are opened downward so as to rectilinearly guide a door roller 3 that is installed on an upper end of a window frame and has a vertical shaft 3a or a diagonal shaft 3b, have guides 4 that are vertically or diagonally formed at both sides thereof, and are rectilinearly formed to have a predetermined length; and one or more upper meandering rail units 2 which diagonally or curvedly guide an upper door roller 3, which rectilinearly moves on the upper linear rail unit 1, so as to operate the window frame in a horizontal direction, are installed to be connected to one side end of the upper linear rail unit 1 so as to be connected to the guides 4 of the upper linear rail unit 1 with the same cross section, and have guides 4 that are diagonally or curvedly extended.