A rapid spectrodensitometric method is described for the determination of penicillin V in penicillin V benzathine oral suspension. Penicillin V is separated from benzathine, common additives and closely related degradation products on HPTLC-F254 plates using acetone-chloroform-acetic acid (10 + 9 + 1). Quantitative determinations are made using a spectrodensitometer at 230 nm. The proposed method is more sensitive than the official method.