To enrich the cytogenetics of Odontobutis sinensis and provide fundamental information for the establishment of the germplasm standard,breeding of O. sinensis and evolution of Odontobutidae species,karyotype of O. sinensis collected from Liangzi Lake were analyzed by intraperitoneal injection of PHA and colchicines,cultivation in vivo and slides preparation with airdrying and Giemsa staining. The erythrocyte nuclear DNA content (2.50 pg/2C) of Gallus sp. was used as the standard reference,and the erythrocyte nuclear DNA content of O. sinensis were measured by flow cytometry. Cytogenetic analysis of O. sinensis inferred a diploid chromosome number of 2n=44,with a chromosome formula equal to 44T (NF=44),irrespective of sex. The karyotype exhibited large and small chromosome pairs:telocentric pairs 1 (5.914%) and telocentic pair 22 (3.332%). Neither the secondary constriction nor the satellites were found. Nuclear DNA content analysis of O. sinensis suggested an average value of 2.38 pg/2C,while the genome size of the species was 1.17×109 bp. 