Abstract: Based on the long bud stage phenotype of a new Lonicera japonica Flos variety "Huajin 6", using "Huajin 6" and "Da Mao Hua" as materials, probing the mechanism of its phenotype formation. Detection of endogenous Jasmonic acid hormones (JAs) content; the genes related to jasmonic acid (JA) synthesis were identified by transcriptome analysis of Lonicera japonica; flower buds and flowers of "Huajin 6" and "Da Mao Hua" were collected at different periods, and the qRT-PCR (quantitative real-time PCR) technique was used to analyze the trend of the expression of synthesis-related enzyme genes in Lonicera japonica Flos during the bud stage. The study found that the content of JAs in "Huajin 6" Lonicera japonica Flos was significantly lower than that in "Da Mao Hua"; applying exogenous methyl-jasmonate (MeJA) to "Huajin 6" can restore its flowering phenotype, making it close to wild type Lonicera japonica Flos; there are significant differences in the expression of two allene oxide synthase genes (AOS), three lipoxygenase genes (LOX), and two allene oxide cyclase genes (AOC) in the flowers and buds of "Huajin 6" and "Da Mao Hua" at different periods. It is hypothesized that the low expression of JA synthesis-related enzyme genes in " Huajin 6" leads to the blockage of JA synthesis, which causes the formation of the long bud phenotype. This study laid a certain foundation for the genetic breeding of Lonicera japonica, provided a new idea for the improvement of Lonicera japonica varieties, and provided a reference for the study of JAs in plant flower organs.