An assembly type railing inserting and positioning device solves the problem that an existing railing can not be assembled and disassembled freely, and therefore later change can not be made. The device comprises a connecting component used for positioning a railing on a frame body and is characterized in that the connecting component is composed of telescopic limiting pins, a shell body fixed to the two ends of an inner cavity of the railing and used for installation of the limiting pins, and reset springs, the end, fixedly connected with one end of a limiting plate, of each limiting pin penetrates through a through hole of a front baffle of the shell body to be inserted into a through hole, opposite to the through hole in the front baffle of the shell body, in the frame body, the two ends of the tailing are assembled on two opposite sides of the frame body through the limiting pins extending out, the end, sleeved with the corresponding reset spring, of each limiting pin penetrates through a through hole in a rear baffle of the shell body, and the limiting pins are driven through compression or extension of the reset springs to move in a reciprocating mode along the axes of the through holes of the front baffles and rear baffles to get away or be inserted into through holes of the frame body, so that assembly and disassembly of the railing and the frame body are achieved. The device is reasonable in structural design, flexible in assembly and disassembly, convenient to operate, reliable in connection, and capable of reducing manufacturing cost and maintaining cost and making a building look more attractive overall.