Shear wave velocity has been commonly used as one of the important design parameters for geotechnical structures which are subjected to dynamic loading. This paper introduces the development and application of a new apparatus, the Field Velocity Probe (FVP) for measurement of shear wave velocity in the field. The shape of the FVP is a blade with two frames, with transducers installed at the tip of the frames. The shear wave velocity is the ratio of the travel distance to the travel time of the shear waves. Thus, no inversion process is required. Penetration tests have been carried out to assess the applicability and disturbance effects in a calibration chamber. In calibration chamber tests, reconstituted clay is mixed with water using a slurry mixer to compose a model soil with a water content of 110 %. After consolidation of the reconstituted clay, FVP, downhole, and crosshole velocity tests are carried out at 1cm intervals during penetration of the penetrometers. The comparison tests produced similar shear wave velocity profiles for each of the apparatus. Shear wave velocity measurements in the field are measured every 10cm in clay soils up to 30 m by the FVP. The field tests show that the FVP produces a detailed shear wave velocity profile in clay. This study suggests that FVP may be an effective device for measuring the shear wave velocity with minimized disturbance in soft clay.