A　new　sisomicin　resistance　gene　sisR　was　cloned　from　sisomicin-producing　Micromonospora　inyoensis.　The　sisR　fragment　was　obtained　by　PCR　amplification.　The　primer　pairs　were　designed　based　on　grm　gene　sequence　from　gentamicin-producing　Micromonospora　purpurea.　The　template　DNA　was　isolated　from　Micromonospora　inyoensis.　A　series　of　different　DNA　fragments　were　amplified　by　PCR,　which　were　sub-cloned　to　vector　pUC19　for　further　identification.　It　was　found　that　five　specific　transformants　containing　target　DNA　fragments　could　resist　high　concentrations　of　sisomicin　(over　1000　microg/mL　sisomicin).　One　of　them　designated　as　sisR,　was　then　sequenced　and　the　alignment　among　sisR　and　other　related　genes　showed　that　sisR　gene　differs　from　any　known　genes.　It　was　concluded　that　sisR　gene　is　a　sequence　that　has　not　been　reported　so　far.