Genetic evaluation of germplasm collections is an important foundation for crop improvement. Due to the importance of rice as a major world crop, the deep studies or genetic evaluation of Oryza sativa has attracted great interest. This study was conducted to evaluate the genetic identity of five rice landraces from South Kalimantan’s tidal swamp area based on chromosomal character. The chromosomal study was carried out using a modified squash method. The construction of karyotype was done by following procedure of Levan et al. (1964). Results found that mitosis period of all samples mainly occurred from 12.00 to 13.00 a.m. (WITA-Center Indonesia Time). Prometaphase stages of rice landraces was commonly found at 12.30 a.m. (WITA). Results also found that all of rice landraces have chromosomal numbers of 2n=24 (diploid), with the differences of chromosomal character (karyotype). Adil ganal is the variety that has unique chromosomal character of 23 metacentric and 1 submetacentric (11m+1sm) chromosomes with satellite found on this study. Whereas, Siam Unus and Siam Gadis are the local rice varieties that have primitive chromosome type of 24 metacentric (24m+0). The results of this study would provide valuable information for crop improvement or rice breeding program in future.