Objective:To detect and analyze the genetic etiology of retinoblastoma patients, and to provide a theoretical basis for gene diagnosis, genetic counseling and prenatal diagnosis of patients and theirfamilies.Methods:This was an experimental study. Clinical material from 12 families were collected and genomic DNA was extracted from the peripheral blood of patients and related subjects. An FFPE sample was collected from adeceased patient and genomic DNA was extracted. Genomic DNA was extracted from the amniotic ?uid cells of the pregnant women. The mutation was screened by using targeted sequencing,and PCR-Sanger sequencing was used to verify the selected mutations. PubMed and related databases were searched. Pathogenic analysis of the mutation and the mutation effect was interpreted by protein prediction software. The pathogenicity of candidate mutations was determined and graded according to a joint consensus recommended by the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. According to the pathogenic mutation of the proband in the family, the relatedpregnant women underwentRB1gene prenatal diagnosis.Results:Different pathogenic gene variations,6 of which were known pathogenic variations, were detected in 8 of the 12 selected families, and the positive rate was 67%. And theRB1gene c.2404dupG (p.N803Efs*12) and c.1380_1381insCTTA (p.K462Tfs*2)detected in this study were novel genes. All of them were pathogenic based on comprehensive analysisof the eight differentRB1gene mutations detected in this study.Conclusions:Eight of the twelve families with retinoblastoma were diagnosed withRB1mutation. The study found two new mutations in retinoblastoma. Based on the results of the genetic diagnosis, the related families received effective genetic counseling and prenatal diagnosis.