The distribution of phage types among 221 human strains of Salmonella paratyphi A in Indonesia was studied. Approximately 50% were phage type 5, a rare type elsewhere in the world. Most other isolates were the cosmopolitan phage type 1. The ratio of phage type 1–5 was compared for two cities on Java, Jakarta and Yogyakarta. The ratios were significantly different, phage type 5 predominating in Jakarta. The ratio of phage types among 10 S. paratyphi A strains isolated from Jakarta river water was similar to that found in Jakarta patients.