The present invention discloses a breeding method for obtaining heterosis in lined seahorses, which comprises the following steps: S1, selecting parents of lined seahorse from populations with great differences in genetic background； S2, intensified rearing the parents before pregnancy； S3, matching and breeding the parents of lined seahorse from different geographical populations according to complete diallel cross method； S4, finely nursing pregnant seahorses； S5, respectively collecting all postlarvae (filial generations) hatched by each breeding group in one week； S6, rearing the filial generations； and S7, comparing survival rate and growth performance of filial generations. The present invention, via hybridization of different geographical populations to obtain lined seahorse, makes effective use of heterosis. Survival rate and growth rate of filial generations are apparently enhanced compared to that of those filial generations without hybridization. Such method enhances genetic diversity of lined seahorses and accelerates breeding of fine strain of lined seahorses.
