We are developing a new type of wiggler named the edge-focusing (EF) wiggler, which produces the strong transverse focusing field incorporated with the normal wiggler field. The idea of the EF wiggler* and development of permanent magnet blocks with small magnetization errors for the wiggler** were reported at the two preceding FEL conferences. We have fabricated the first model of the EF wiggler to evaluate its performance. It is a five-period planar wiggler with an edge angle of 2 degrees and a period length of 60 mm. The magnetic field in the wiggler is measured with a Hole probe at a magnet gap of 30 mm. It is experimentally confirmed that a high field gradient of 1.0 T /m is realized along the beam axis in the EF wiggler. In this paper, we will report results of the magnetic field measurement and its analysis for the first mode of the EF wiggler.