The invention relates to a lamp post slider installation structure of a lighthouse, which comprises a lamp post; the lamp post is hollow; the structure is characterized in that two or more than two groove holes are arranged in the outer wall of the tail end of the lamp post; one ends of the groove holes are open; a bottom plate is fixedly arranged in the inner cavity of the tail end of the lamp post; the distance between the bottom plate and the opening at the bottom end of the lamp post is more than the lengths of the groove holes; the groove holes are provided with corresponding sliders; the sliders are arranged on the groove holes; a seal plate is also arranged; the seal plate is provided with a plurality of through holes corresponding to the bottom plate; nuts which are matched with the through holes are respectively and fixedly arranged on the through holes of the bottom plate towards the direction of the bottom end of the lamp post; bolts penetrate through the seal plate and are connected with the nuts which are fixedly arranged on the bottom plate; and the sliders are fixedly arranged between the seal plate and the bottom plate. The lamp post slider installation structure of the lighthouse has the beneficial effects that the whole structure is stable, the installation is convenient, and the operability is strong.