A self-destructive syringe with drug dissolved for once comprises a needle (1), a cylinder (2), a core rod (3), a first ratchet groove (4), a second ratchet groove (5), a third ratchet groove (6), a fourth ratchet groove (7), a mounting hole (8), a non-return element (9), a non-return pike (10), a ratchet (11), a sealing plug (12), reciprocating parts (13, 14), a break part (15) and graduation lines (16). The needle (1) is adhered on the cylinder (2) or a needle holder with the needle (1) is sleeved on the cylinder (2), the non-return element (9) is mounted in the slot of the core rod (3) through the mounting hole (8), and mounted between the third ratchet groove (6) and the fourth ratchet groove (7).
