This　paper　presents　a　novel　method　for　protecting　H.264/AVC　streaming.　The　issues　on　the　compression　domain　video　encryption　have　been　pointed　out　and　fully　addressed.　To　optimize　the　tradeoff　between　security　level　and　computational　complexity,　only　the　most　significant　bits　for　reconstructed　video　quality　in　H.264/AVC　streaming　are　extracted　and　encrypted,　including　the　codewords　of　intra-prediction　mode,　the　low　frequency　DCT　coefficient　of　intra-frames　and　motion　vector　difference　(MVD).　To　keep　the　encrypted　streaming　format-compliance　to　the　H.264/AVC　standard　decoder,　the　codewords　of　intra-prediction　mode　are　encrypted　with　IPME,　the　sign　bit　of　the　codewords　of　DCT　coefficient　are　encrypted　and　the　info-suffix　of　the　codewords　of　MVD　are　encrypted.　Experimental　results　show　that　the　proposed　scheme　exhibits　significant　computational　efficiency　and　reliable　security,　can　resist　not　only　perceptual　attacks　but　also　brute-force　attacks.　Thus,　the　proposed　scheme　will　be　well　suited　for　real-time　and　resource-limited　systems.　©　2012　GIRI.