Abstract: The experiments on effects of temperature on larval survival and development of Scylla serrate were conducted by laboratory maintaining larvae from hatching to first juvenile crab stage under a set of constant temperatures(5℃ -35℃ ). The results showed that 25-30℃ were optimum for zoea. When tempe-rature was 20℃ , the zoea-1 could survive as long as 16 days, in the meanwhile temperature was≥35℃ , no larvae could survive more than 5 days, mass mortality was found in above both cases, and at 35℃ , no larvae could molt into zoea-3; at 18 and 20℃, all larvae died within zoea--3. The zaea-1 was more tolerant to lower temperatures (≤20℃) than successive stages and the survival rate for zaearl was hightest at 25℃, but after zoear-1，the mortality rates were relatively lower at 28℃ and 30℃. From hatching to metamorphosis finished,the duration of mean develop-ment at 30℃ was only 17 days, whereas it was 23 days at 25℃.Metamorphosis from zoea to megalopa was adversely effected when temperas-ture was≥34℃ , whereas successful metamorphsis was observed at 20--27 ℃ . How-ever, after metamorphosis, data show that megalopa is more tolerant to higher temperatures than zoea. At 35℃ , no adverse effect on larvae survival was found while the duration of megalapa was greatly shortened (at 35℃ , 6--8 days; at 20℃ ,22 days).Higher rate of"extra instar"(zoea-6)appeared at 25℃ which is suboptimal for later zneal instars.