Objective To detect characteristics and the pathogenesis of rhodopsin (RHO) gene mutation in an inbreeding family with autosomal recessive retinitis pigmentosa (ARRP). Methods Peripheral venous blood 5-8 ml was abstracted from 8 members in the inbreeding ARRP family and 10 control individuals. DNA gene group was picked. Extron 1-5 of RHO gene was amplified by polymerase chain reaction (PCR),and the mutation of RHO gene was screened by direct DNA sequence measurement. Results The Gln-344-Arg mutation in the RHO gene was detected in 3 patients with ARRP and homozygotes of the mutation in 3 patients were found. Heterozygous of the mutation was detected in the parent of patients and 1 healthy family member. No mutation of RHO gene was found in 2 healthy family members and 10 control individuals. Conclusions The Gln-344-Arg mutation in the RHO gene may be the pathogenic factor of the ARRP family; the frequency of the mutation of RHO gene may increase in the in breeding ARRP family.(Chin J Ocul Fundus Dis,2004,20:145-148)