Genetic similarity and diversity of Asian catfish Clarias batrachus populations collected from hatchery and wild stocks were examined using randomly amplified polymorphic DNA polymerase chain reaction (RAPD-PCR). Out of l6 primers tested, 5 primers produced 1376 RAPD bands ranging from 8.1 to 13.71 polymorphic bands per primer. The polymorphic bands in these populations ranged from 56.4% to 59.6%. Polymorphic bands per lane within populations ranged from 4.88 to 5.3%. The similarity within the population from wild varied from 0.40 to 0.83 with a mean (±SE) of 0.57 ±0.08. The level of band sharing values was 0.59 ±0.07 within the catfish population from hatchery. However, in view of band sharing values, polymorphic bands and also the specific major bands genetic differentiation between these populations were present even if band sharing (BS) values were somewhat marginally different and good genetic divergence existed in both catfish populations. Therefore, the number of RAPD polymorphisms identified in this study may be sufficient to permit estimating genetic similarity and diversity.