Development of highly sensitive and reliable method for detection of phytohormones is of great significance to study plant hormones and agricultural production. In this study, an ultra-high-performance liquid chromatography-mass spectrometry/ mass spectrometry method was established for separation and quantification of trans-zeatin, trans-zeatin riboside, gibberellin A3, indol-3-acetic acid, salicylic acid, abscisic acid, and jasmonic acid (JA) without any label. The separation was performed on an Agilent Explus Plus C18 column by using methanol and water as mobile phases with gradient elution. The target compounds were confirmed and quantified by mass spectrum via positive electrospray ionization for trans-zeatin, transzeatin riboside, indole-3-acetic acid, and via negative electrospray ionization for gibberellin3, salicylic acid, abscisic acid, and JA. The limits of detection ranged from 0.0127 ng L–1 for gibberellin A3 (GA3) to 33.26 ng L–1 for JA and were lower than the currently reported values in literature. The proposed method was applied for qualitative and quantitative analyses of phytohormones in peanut gynophores and pods. The recoveries of the spiked phytohormones ranged from 80.20 to 102.56％. The contents of seven endogenous hormones varied specifically in different development stages of peanuts. This study provides a highly sensitive and selective detection method for hormones and elucidates the growth and development of the gynophore and peanut fruit, which are controlled by seven endogenous hormones.