In　this　paper,　we　introduce　matrix-valued　multiresolution　analysis　and　orthogonal　matrix-valued　wavelets　with　arbitrary　integer　dilation　factor　m.　A　necessary　and　sufficient　condition　on　the　existence　of　orthogonal　matrix-valued　wavelets　is　derived　by　virtue　of　paraunitary　vector　filter　bank　theory.　An　algorithm　for　constructing　compactly　supported　m-scale　orthogonal　matrix-valued　wavelets　is　presented.　The　notion　of　orthogonal　matrix-valued　wavelet　packets　is　proposed.　Their　properties　are　investigated　by　means　of　time-frequency　method,　operator　theory　and　matrix　theory.　In　particular,　it　is　shown　how　to　construct　various　orthonormal　bases　of　space　L(2)　(R,　C(rxr))　from　these　wavelet　packets,　and　the　orthogonal　decomposition　relation　is　also　given.　(C)　2007　Elsevier　Ltd.　All　rights　reserved.