The utility model discloses an installation structure of a tunnel illuminating lamp. The installation structure comprises an installation frame. When the lighting lamp body is installed, the lamp body fixedly provided with the fixing ring and the L-shaped clamping plate is pushed upwards to a proper position along the installation groove of the installation frame, and then the lamp body is rotated leftwards to drive the fixing ring and the L-shaped clamping plate to move leftwards. After the inclined opening of the L-shaped clamping plate makes contact with the inserting column, upward pressure is generated, the inserting column moves upwards, the connecting movable plate is driven to ascend along the movable groove, the reset spring is stretched, and meanwhile the linkage ring and the holding ring are driven to move upwards. When an L-shaped clamping plate moves leftwards in place, an inserting hole is located below an inserting column,
extrusion force disappears, a reset spring rebounds, the inserting column, a connecting moving plate, a linkage ring and a holding ring are driven to move downwards till the inserting column makes contact with the inserting hole, the illumination lamp body can be installed and fixed, and therefore the illumination lamp has the
advantage of being convenient to install and fix; and the tunnel illuminating lamp can be quickly mounted and fixed, and the mounting and fixing time of the tunnel illuminating lamp is shortened.