In the present paper, we discuss various techniques for measuring velocity fields in incompressible turbulent boundary layer by means of PIV and particle tracking. In particular, key features for performing measurements in the vicinity of streamlined surface are considered. A description of the optical measuring system and method of flow seeding with tracer particles is presented. Results of measurements for flow velocity fields in boundary layer on a flat plate are analyzed in the paper. Comparative data illustrating the efficiency of various algorithms for particle images interrogation is presented. Some of the results on application of the abovementioned techniques for diagnostics of the boundary layer, modified by air injection through microperforated surface, are also presented in the paper.