A tension adjusting device for orthodontic maintainer, which includes a slide rail assembly, a guide tube, a compression spring and two connecting blocks. The slide rail assembly is provided with two selectively movable displacements on two connecting sections of the slide rail Positioning component, the guide tube and the slide rail are arranged in parallel and a compression spring is installed in the guide tube, the two connecting blocks can be installed on the outer side of the slide rail and the guide tube relatively linearly, and the two ends of the compression spring are respectively elastically pushed Against the two connecting blocks, the positioning component of the slide rail assembly can selectively protrude into the long hole of the connecting block to resist the limit position, so that the positioning component can be directly sunk into the slide rail by another positioning component, and the length of the connecting block can be adjusted by another positioning component The simple way that the hole resists the limit position changes the relative position of the two connection blocks.一種牙齒矯正維持器之張力調整裝置，其包括滑軌組件、導引管、壓縮彈簧及兩連接塊，滑軌組件於其滑軌的兩連接區段上各裝設有能選擇性升降位移的定位部件，導引管與滑軌平行設置且導引管內裝設壓縮彈簧，兩連接塊係能相對直線滑移地裝設於滑軌與導引管的外側，壓縮彈簧兩端分別彈性推抵兩連接塊，滑軌組件的定位部件能選擇性凸伸至連接塊的長孔中抵止限位，藉以利用改變定位部件直接沉置滑軌中，由另一定位部件對連接塊的長孔抵止限位之簡便方式，改變兩所述連接塊的相對位置。
