The lifetime of the 5p2P3/2 level of Sr+ has been measured using the zero field level crossing (Hanle effect) technique with optical excitation from the ground state of the ion. The ions are produced in a discharge at the mouth of a furnace used to produce a strontium beam. No foreign gas is used to carry the discharge. An alignment depolarization cross section is obtained for collisions between Sr+ ions and Sr neutral atoms. The results are compared with the published ones.