An　imaging　system　of　ultrasonic　detection　is　presented　for　non-destructive　testing　(NDT)　of　complex　structures　by　using　virtual　instrument　technology.　The　control　devices　for　C-scan　as　well　as　for　imaging　system　are　designed　and　manufactured.　In　the　coarse　scan　mode　with　the　scan　step　of　1　mm,　the　system　can　quickly　give　an　image　display　of　a　cross　section　of　80　mm　(L)　×60　mm　(D)　by　one　measurement.　In　the　refined　scan　model,　the　system　can　show　a　refine　image　of　the　coin.　All　experiments　on　coin,　bulk　metal,　and　other　forms　of　specimen　verify　the　efficiency　of　the　proposed　method.　The　experimental　results　are　accurate　and　reliable.　©　(2013)　Trans　Tech　Publications,　Switzerland.