A　unified　boundary　integral　equation　is　proposed　to　solve　the　sound　radiation　and　scattering　from　the　open/closed　thin-bodies　with　arbitrary　acoustic　impedance　in　two-　and　three-dimensional　domain.　The　proposed　integral　equation　has　the　same　influence　matrix　for　both　acoustic　radiation　and　scattering　problems　and　can　synchronously　solve　the　sound　radiation　and　scattering　from　non-compact　thin-body　with　arbitrary　acoustic　impedance　condition,　which　can　be　applied　to　predict　the　noise　of　turbomachinery,　pipe,　and　the　muffler　performance.　In　further　work,　the　effects　of　moving　surface　and　moving　medium　on　sound　radiation　and　scattering　should　be　considered.