Status of endometrium is a very important factor which influences the implantation of fertilized embryos. In this study, we evaluated the possibility that the endometrial depth and pattern assessed by vaginal sonography on the day of human chorionic gonadotropin (HCG) injection in in vitro fertilization (IVF) cycles could be used to predict the IVF outcome. A total of 112 cycles using gonadotropin releasing hormone agonist (GnRHa) for ovulation induction were evaluated. We classified all patients into group A(<9mm) or group B(${geq}$ 9mm) according to endometrial depth, and into group l(hyperechogenic), group 2(isoechogenic) or group 3(hypoechogenic and triple line) according to endometrial pattern. The other classification was made considering both endometrial depth and pattern. There was no significant correlation between serum estradiol level and endometrial sonographic findings(depth and pattern)(p>0.05). The pregnancy rate of group A(31.3%) did not differ significantly from that of group B(43.7%), but no pregnancies were found in any patients with endometrial depth less than 6mm. The pregnancy rate was 40%, 35.7%, and 44.6 % for group 1, gorup 2, and group 3, respectively, but there was no statistically significant difference between these groups(p>0.05). In combined classification, there was a trend of higher pregnancy rate in case of endometrial depth greater than 9mm and hypoechogenic triple line pattern, but there was no statistically significant differences between these groups(p>0.05). The conclusion from the present data is that endometrial ultrasonography on the day of hCG administration had no predictive value for conception in IVF cycles.