The invention relates to a table lifting structure, comprising a base, a lower rod body, an upper rod body, a table board unit, a positioning device, and the lower rod body has a first hollow portion, the first hollow portion has a relative The inner wall of the upper rod body has a second hollow portion, the upper rod body can be inserted into the first hollow portion and corresponding to the lower and lower parts of the lower rod body, and the through holes are disposed on opposite sides； The positioning device comprises a positioning seat, a scroll spring, a working cable and a control button. The positioning seat is arranged at the bottom of the upper rod body, and comprises two shells which can be oppositely combined. a two-cylinder body, an actuating rod and an elastic body； the scroll spring is disposed on the casing, one end is engaged with the top end of the lower rod body, and one end of the moving cable is engaged with the actuating rod of the positioning seat, and the other end portion is Engaged with the control button, and the control button can be used to move the moving cable, the actuating rod, and the latch body to cause the card body to be stuck or not to be pulled down； thereby, the present invention can have better positioning stability and convenient operation.本發明係一種桌體升降結構，包括一底座、一下桿體、一上桿體、一桌板單元、一定位裝置，並該下桿體中央具第一中空部，該第一中空部具相對之內壁；又該上桿體中央具第二中空部，該上桿體可穿插於第一中空部內並對應下桿體上、下位移，又於相對二側設置透孔；又該桌板單元與上桿體上方接合；又該定位裝置包括一定位座、一渦捲簧片、一作動索、一控制鈕，該定位座設於上桿體底部，包括二可相對組合之殼體、二卡掣體、一作動桿、一彈性體；又該渦捲簧片設於殼體上，一端與下桿體頂端接合，又該作動索一端部與定位座之作動桿接合，另一端部與控制鈕接合，並可由控制鈕帶動作動索、作動桿、卡掣體位移使卡掣體卡掣或不卡掣下桿體；藉此本發明可具較佳定位穩定性及操便利功效。
