The (5p3/2ns)1 (n = 13-21), (5p3/2nd)3 (n = 13-24) autoionizing levels of strontium have been measured by the laser multi-step excitation method and polarization technique. In the core excitation profiles for the (5p3/2ns)1 states below the 5p1/2 ionization limit, distortions appear at locations corresponding to the (5p1/2ns), and (5p1/2nd)1 levels. Distortions also appear in the (5p3/2nd)3 excitation profiles. These results show that there exist interse-ries interactions between the (5pjns) and (5pjnd) autoionizing series of strontium.