As a result of a successful work on intergeneric crossing in fish during the years of 2006 and 2007 in Zhejiang Institute of Freshwater Fisheries, a hybrid F₁ of Erythroculter ilishaeformis♀×Megalobrama amblycephal ♂ were obtained. Further comparative analysis of morphological characteristics, karyotypes and gene groups were carried out to clarify the differences of morphological and genetic traits between the hybrid and its parents. The results are as follows, (1) both fertilizing rates and hatching rates by crossing of E.ilishaeformis♀× M.amblycephal ♂ were above 90%, which indicates a good kin ability between female E.ilishaeformis and male M.amblycephal; (2) most numeric traits of the hybrid F₁ appeared to be medium. Among ten countable traits, the numbers of gill rake and lateral scale are within the range of its parents’, the average hybrid index is calculated to be 54.56, which interprets that the countable traits approach to the middle values and slightly incline to its male brood’s. Of seventeen measurable traits, nine traits are significantly different to its parents’, including four traits incline to paternity, three to maternity and two deviate from its parents’. The average hybrid index is calculated to be 49.59, which indicates the measurable traits are also close to the middle values. Cluster analysis and discriminant analysis of body frame indexes denote that the body shape of hybrid F1 has obvious differences from its parents, appears to be of mid-type and be affected more by its maternity; (3) Chromosome numbers (2n) of the hybrid F1 are counted to be 48 and karyotype formula are described as 18m+26sm+4st (NF=92), which is similar to those of its parents. The observations specify that the hybrid F1 is a diploid with fertility; (4) Most RAPD enlargement stripes of the hybrid F1 could be found in both parents and some are solely from either paternity or maternity, which shows a hybrid in nature. The hybrid F1 has a relative heredity distance of 0.4327 from the maternity and 0.2312 from its paternity. The former is farther than the later, which elucidate that the hybrid F1 has an unequal heredity difference to its parents and a genetic inclination to its paternity. This is also supported by UPGMA.