【Objective】 The large-scale production and application of the new Pinus elliottii × P. caribaea hybrid requires the application of an efficient somatic embryogenesis system. Immature zygotic embryos were used as explants to investigate which key factors influence somatic embryogenesis during embryogenic callus induction, proliferation, maturation, germination and plantlet acclimatization,establishing a comprehensive protocol for efficient SE propagation of this economically important hybrid.【Method】A total of four representative genotyes of Pinus elliottii × P. caribea were used as starting material to investigate the main factors that affect the induction of embryogenic callus: including genotype, zygotic embryo developmental stage (June 2nd to 23 rd), basic culture medium(DCR, LP, MSG and BM), hormone type and concentration, etc. Well developing embryogenic callus was analyzed for somatic embryo maturation, germination and plant regeneration. Ultimately, regenerated plants were obtained.【Result】All investigated factors (genotype, developmental stage, basic culture medium, hormone (PGR) combination and concentration) were found to have significant effects on embryogenic callus induction. The optimal time to collect explants was from June 9th to 23rd: the multi-embryo division to early cotyledon stage. The optimal embryogenic callus induction medium is DCR with 2.0 mg/L 2,4-D,1.0 mg/L BA and 0.5 mg/L KT. The average induction rate was 19.51%. To maintain the embryonic callus in a proliferative state, capable of differentiation, for a prolonged amount of time, a solid-liquid alternating culture protocol and reduced hormone concentration in the proliferation medium was required. The optimal proliferation medium was modified P6, supplemented with 0.8 mg/L 2,4-D, 0.5 mg/L BA and 0.5 mg/L KT on the solid culture medium and in the first-time liquid culture medium. During the subsequent liquid culture process, the hormone concentration should be gradually reduced. The optimal culture media for somatic embryo maturation was modified P6, with 10.0 mg/L ABA, 10.0 mg/L GA, 0.2 mg/L 2,4-D, 4 000 mg/L inositol and 2.0 mg/L activated carbon(AC). 298 mature somatic embryos were induced per mL of packed cell volume (PCV) embryogenic callus at the maturation culture cycle (6-7 weeks). Drying treatment inhibited the germination of somatic embryos, and the germination rate was best when cultured on 1/2 DCR, supplemented with 0.2 mg/L NAA, 0.5 mg/L BA and 2.0 mg/L activated carbon. Successfully germinating somatic embryos were transferred to the following medium for further cultivation until they reached 3-4 cm in height with true leaves: 1/2 DCR + 0.1 mg/L NAA+ 0.5 mg/L BA +2.5 g/L AC. Finally, the matured plantlets were transplanted and hardened onto a volume ratio of 1∶1∶1 of river sand∶perlite∶peat soil substrate and grown into robust 7-8 cm tall plants over the course of one month. 【Conclusion】In this study a complete and efficient somatic embryogenesis system for the P. elliottii × P. caribaea hybrid has been established. Furthermore, a more efficient method for embryogenic callus maintenance, using solid-liquid-solid alternating culture, has been developed. This system provides a foundational platform for large-scale clonal propagation of hybrid, with potential applications in forestation, genetic conservation, and bioreactor-based propagation systems.