We have observed pressure-induced superconductivity of iodine at the f
irst and the second atomic phase under pressures exceeding 22 GPa at t
emperatures below 1.2 K. The transition to the superconducting state i
s confirmed by both resistance and magnetization measurements. Negativ
e pressure dependence of Tc is observed in monatomic state, but no sup
erconductivity is observed in molecular state.