In　this　article,　three　dimensional　Kirchhoff　inverse　scattering　method　is　modified　to　convenient　form　for　two　cylindrical　specimens　that　include　three　dimensional　defects.　Two　Aluminum　cylinders　with　flaw　models　are　prepared　and　ultrasonic　measurements　are　carried　out.　The　measurement　area　in　the　modified　methods　is　restricted　in　the　plane　perpendicular　to　the　axis　of　cylindrical　specimen.　That　to　say　that　the　method　is　modified　to　convenient　form　to　use　measured　waveforms　in　the　x(1)-x(2)　plane.　The　measured　wave　data　are　fed　into　the　inversion　method　and　cross-sectional　images　are　obtained.　At　the　same　time,　we　get　the　numerical　results　from　all　directions　by　finite　element　method　From　the　numerical　analysis　and　experimental　research　for　two　kinds　of　defects,　it　is　verified　that　the　Kirchhoff　inversion　works　well　for　both　volumetric　defects　and　surface　defects.