Abstract  [Aim]  To determine the sequence structure and spatiotemporal expression patterns of four key insulin signaling pathway genes in Propylea japonica. [Methods]  The E(sev)2B, TOR, PDK1 and PI3K genes were identified in the genome of P. japonica and their coded amino sequences and functional domain locations analyzed. Expression profiles of these genes in different developmental stages (1st, 3rd, 5th and 7th day after eclosion) and tissues (head, thorax, abdomen and gut) were investigated using real-time quantitative PCR. [Results]  Expression levels of all four genes peaked on the 7th day after adult emergence. Expression levels of the E(sev)2B and PI3K genes were significantly higher in the gut than in the head, thorax and abdomen on the 1st, 3rd and 5th day after emergence (P < 0.05). Expression levels of the TOR gene in the thorax, abdomen and gut were significantly higher than in the head on the 1st day after emergence (P < 0.05). Expression of the PDK1 gene was highest in the gut on the 3rd and 5th day after emergence, significantly higher than in the head, thorax and abdomen (P < 0.05). [Conclusion]  Expression patterns of the E(sev)2B, TOR, PDK1 and PI3K genes differed in different developmental stages and tissues of P. japonica. This finding lays a foundation for further research on the role of the insulin signaling pathway in the reproductive development of this species.