The bamboo grasshopper, Rammeacris kiangsu Tsai (Orthoptera: Arcypteridae), is an important pest attacking various species of bamboos including Phyllostachys pubescens and Bambusa textilis. It is widely distributed in many provinces of China, including Jiangshu, Zhejiang, Anhui, Sichuan, Hubei, Hunan, Fujian, Guangdong and several others. It is known to be univoltine across its range of distribution and overwinters as eggs. In this article, we investigated the characteristics of its diapause development, including effects of constant temperatures and low-temperature treatments on egg hatching, and embryonic development, water content, supercooling point of the eggs. The results showed that the species has a prolonged pre-hatching period of eggs and an irregular hatching under different constant temperatures. Chilling at 8 ℃ for 30, 60, or 90 days had an increasingly evident effect promoting egg development, resulting in increasingly shorter pre-hatching period of eggs. These results indicated that egg diapause occurred in R. kiangsu and low temperature could decrease the intensity of diapause. When egg pods produced by adults reared in wood-framed cages at 25℃ and LD 16: 8 h in a greenhouse were incubated at 25℃, the embryos showed continuous development, as measured by embryonic head width, antennae and body length, within the first 40 days, followed by a period of obvious developmental stagnation, and resumed from about day 80 after deposition. The results suggested that the embryonic development R. kiangsu could be divided into three stages, i.e. pre-diapause developmental stage, diapause stage and post-diapause developmental stage under 25℃. Eggs entered diapause about 40 days after deposition and reached a deep-diapause stage from 40 to 75 days. The eggs had very low water content immediately after spawning, experienced a quick water absorption period about 25 days after deposition, and showed no obvious water content increase subsequently, indicating water absorption of eggs takes place before diapause. The supercooling point varied depending on the developmental stages of the eggs, being about -20℃ in pre-diapause developmental stage, decreasing remarkably in diapause stage, and resuming in post-diapause stage, suggesting that cold tolerance of overwintering eggs was closely related to diapause in R. kiangsu.