Abstract: To explore dynamic genetic mechanism of panicle length in rice, mapping quantitative trait loci (QTLs) and gene × environment interaction analysis were used to research panicle length from a RIL including 130 lines deriving from Milyang 46 and FJCD during grain filling. This research work was carried in Wuyishan City and Putian City, Fujian Province. 35 additive QTLs were detected in two environments, located in chromosome 1, 2, 4, 5, 7, 8, 9, 10, 11, and contribution rates for phenotype variance were from 0.5% to 16.52%. We got 16 QTLs with significant additive × environment interaction effects, located in chromosome 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, and most of them were minor QTLs. In Wuyishan, 1 pairs of epistatic QTLs was detected, and the contribution rate for phenotypic variation was 33.14%. This study aimed to reveal dynamic expression of QTLs controlling panicle length in rice under different environmental conditions, and benefited to rice breeding.