1. A waterproof button structure, comprising a button main body, a shell and a shaft sleeve, wherein a button mounting slot is reserved on the shell; a vertical column is arranged in the button mounting slot; the vertical column is provided with a through hole longitudinally penetrating through the vertical column; the button main body comprises a pressing portion and a shaft portion connected to a bottom surface of the pressing portion; the bottom surface of the pressing portion is provided with a first annular groove surrounding the shaft portion; a second annular groove is formed between the vertical column and an inner wall of the button mounting slot; a sealing ring groove is arranged on the shaft portion; the sealing ring groove is sleeved with a first sealing ring; the shaft portion is connected with the shaft sleeve after passing through the through hole; the first sealing ring resists against an inner wall of the through hole; a second sealing ring sleeves an outer circumferential side of the shaft sleeve; a third annular groove is formed in a bottom of the shell; the third annular groove surrounds a bottom of the through hole; the second sealing ring is provided with an annular bulge matched with the third annular groove; and the annular bulge is embedded into the third annular groove.