This study was conducted to investigate the effects of diet energy on expression of FSHR mRNA in ovary during sexual maturity and laying rates of laying hens. Three hundred and sixty 8-week-old HyLine laying hens were divided into 5 groups with 4 replicates in each group and 18 hens in each replicate. Different energy level diets were confected under the same other nutrient levels. Reverse transcription polymerase chain reaction (RT-PCR) was used to determine the expression of FSHR mRNA in ovary of laying hens during sexual maturity. The results showed that expression of FSHR mRNA in ovary of laying hens of high energy groups increased from 14 to 18 week-old and decreased from 18 to 22 week-old. Expression of FSHR mRNA in ovary of laying hens of control and low energy groups increased with the increase of age. In 14 week-old, expression of FSHR mRNA in low energy Ⅱ group was significantly lower than those in other groups (P<0.05). In 18 week-old, expression of FSHR mRNA in control group was significantly higher than that in low energy Ⅱ group (P<0.05), no significant differences among other groups (low energy Ⅰ, Ⅱ, high energy Ⅰ, Ⅱ) were observed (P>0.05). In 22 weekold, no significant differences among control, high energy Ⅱ and low energy Ⅰ groups were observed (P>0.05), but their expression levels of FSHR mRNA were significantly higher than those in high energy Ⅰ and low energy Ⅱ groups (P<0.05). When the correlation between expression level of FSHR mRNA in ovary of 22 week-old laying hens and laying rates was analyzed, a very significant positive correlation for 22 and 28 week-old (P<0.01), a significant positive correlation for 35 week-old (P<0.05) and no significant correlation for 46 week-old (P>0.05) were obtained, respectively. The results suggested that proper energy level can increase expression of FSHR mRNA in ovary of laying hens and increase the reproductive performance.