The preparation and antigenic property of 3-dehydrolithocholyglycine-bovine serum albumin (BSA) conjugate in which the hapten is linked to the carrier protein through an (O-carboxymethyl) oxime bridge at the C-3 position on the steroid nucleus is described. Antibody raised against antigen in the rabbit possessed high titer and specificity to lithocholylglycine, exhibiting no significant cross-reaction with free lithocholic acid or lithocholyltaurine.