Intra-Body　Communication(IBC)　is　a　short　range　＂wireless＂　communication　technique　appeared　in　recent　years.　This　technique　relies　on　the　conductive　property　of　human　tissue　to　transmit　the　electric　signal　among　human　body.　This　is　beneficial　for　devices　networking　and　sensors　among　human　body,　and　especially　suitable　for　wearable　sensors,　telemedicine　system　and　home　health　care　system　as　in　general　the　data　rates　of　physiologic　parameters　are　low.　In　this　article,　galvanic　coupling　type　IBC　application　on　human　limb　was　investigated　in　both　its　mathematical　model　and　related　experiments.　The　experimental　results　showed　that　the　proposed　mathematical　model　was　capable　in　describing　the　galvanic　coupling　type　IBC　under　low　frequency.　Additionally,　the　calculated　result　and　experimental　result　also　indicated　that　the　electric　signal　induced　by　the　transmitters　of　IBC　can　penetrate　deep　into　human　muscle　and　thus,　provide　an　evident　that　IBC　is　capable　of　acting　as　networking　technique　for　implantable　devices.