Organic acid radical-pillared hydrotalcites of the type of M6Al2(OH)16〔CnH2n+1COO-〕(M=Mg,Zn;n=13,17)have been successfully assembled by calcination of M6Al2(OH)16CO3·mH2O〕(M=Mg,Zn)and rehydration of MgAlO and ZnAlO in tetradecylic acid solvent and stearic acid solvent respectively and characterized by IR and XRD.The experimental results show that the method of calcination-rehydration could be used to prepare the organic acid radical-pillared MAl-LKHs(M=Mg,Zn)which have good crystallinity,regular layered structure and large interlayer distance (d003(M6Al2(OH)16〔CnH2n+1COO-〕)=2.74nm(M=Zn,n=13),2.90nm(M=Mg,n=13),3.24nm(M=Zn,n=17),3.22nm(M=Mg,n=17).