Objective　To investigate the number of follicles and insulin-like growth factor I receptor (IGF-ⅠR) in stimulated cycles. Method　IGF-ⅠR mRNA and IGF-ⅠR in granulosa cells obtained during oocyte retrieval were respectively measured by reverse transcript polymerase chain reaction （RT-PCR） and Western blot technique. Results　The expression of IGF-ⅠR mRNA in poor responders (follicles≤3) was much lower than in normal responders (follicles 4～13) and high responders (follicles≥14) (1.70±0.23, 2.92±0.49,4.22±1.50 respectively). Similar results were obtained for IGF-ⅠR (1.32±0.31, 2.01±0.72, 4.39±2.31 respectively). Conclusion　The expression of IGF-ⅠR correlated with the effects of gonadotropin hormone on follicular development.