Reduction of ethyl 1-benzyl-3-oxo-piperidine-4-carboxylate gave predominantly the cis-(3R,4R) ethyl 1-benzyl-3R-hydroxy-piperidine-4R-carboxylate by most microorganisms as the major product with high diastereo- and enantioselectivities. The two best microorganisms, Candida parapsilosis SC16347 and Pichia  methanolica SC16415, gave the 3R,4R-hydroxy ester with >97% diastereomeric excess and >98% enantiomeric excess. A few microorganisms gave 10-40% of the trans-(3R,4S) ethyl 1-benzyl-3R-hydroxy-piperidine-4S-carboxylate as the minor product.