The　co-doped　MgB2　bulk　samples　have　been　synthesized　using　an　in　situ　reaction　processing.　The　additives　is　8　wt.%　SiC　nano　powders　and　10　wt.%　RCH2CHCOO)(2)Zn](n)　poly　zinc　acrylate　complexes　(PZA).　A　systematic　study　was　performed　on　samples　doped　with　SiC　or　PZA　and　samples　co-doped　with　both　of　them.　The　effects　of　doping　and　co-doping　on　phase　formation,　microstructure,　and　the　variation　of　lattice　parameters　were　studied.　The　amount　of　substituted　carbon,　the　critical　temperature　(T-c)　and　the　critical　current　density　(J(c))　were　determined.　The　calculated　lattice　parameters　show　the　decrease　of　the　a-axis,　while　no　obvious　change　was　detected　for　c-axis　parameter　in　co-doped　samples.　This　indicates　that　the　carbon　was　substituted　by　boron　in　MgB2.　The　amount　of　substituted　carbon　for　the　codoped　sample　shows　an　enhancement　compared　to　that　of　the　both　single　doped　samples.　The　co-doped　samples　perform　the　highest　J(c)　values,　which　reaches　3.3　x　10(4)　A/cm(2)　at　5　K　and　7　T.　It　is　shown　that　co-doping　with　SiC　and　organic　compound　is　an　effective　way　to　further　improve　the　superconducting　properties　of　MgB2.　(C)　2011　Elsevier　B.V.　All　rights　reserved.