The synthesis of a polyamide entirely based on naturally occurring compounds has been carried out by polycondensation of N,N-bis(trimethylsilyl) L-lysine ethyl ester and bis(pentachlorophenyl) di-O-methyl-L-tartrate in a chloroform solution. The new polytartaramide has a molecular weight of similar to 6000, displays high optical activity and is soluble in water. The regioregularity of the polymer has been examined by C-13 n.m.r. with the support of model compounds, which revealed that the chain is predominantly syndioregic in nature.