An efficient heterogeneous gold-catalyzed Sandmeyer coupling of aryldiazonium salts with sodium bromide or thiols for the formation of C-Br and C-S bonds has been achieved in high yields and selectivities under mild conditions by using a bis(diphenylphosphinomethyl)amino-modified mesoporous MCM-41-immobilized gold(I) chloride complex [MCM-41-2Ph2PAuCl] as the catalyst without using sacrificial oxidants. Vital to the success of this C-heteroatom coupling is the nucleophile-promoted activation of aryldiazonium salts, which can serve as an efficient oxidant for the conversion of Au(I) to Au(III) without the use of a photocatalyst or an assisting ligand. This new heterogenized gold(I) complex can be easily prepared by a simple procedure and recovered via centrifugation, and recycled more than seven times without any significant loss of its catalytic efficiency.