Transient elastometry (TE) could provide a more accurate evaluation of the frequency and risk factors of liver fibrosis in hepatitis C virus (HCV) infection than that based on biopsy. The aim of this study was to assess the prevalence of and factors associated with significant liver fibrosis in a large population of HIV/HCV-coinfected patients. HIV/HCV-coinfected patients, who had participated in a cross-sectional, multicenter, retrospective study of liver fibrosis using noninvasive markers and in whom a determination of liver stiffness (LS) by TE was available, were included in this analysis. Factors potentially associated with significant fibrosis (LS ≥ 9 kPa) were analyzed. One thousand three hundred and ten patients fulfilled the inclusion criteria, 526 (40%) of them showed LS ≥ 9 kPa and 316 (24%) cirrhosis (LS ≥ 14 kPa). The factors independently associated with significant fibrosis [adjusted odds ratio (95% confidence interval, P value) were the following: older age [1.04 (1.01-1.07), 0.002], daily alcohol intake > 50 g/day [1.58 (1.10-2.27), 0.013] and the length of HCV infection [1.03 (1.00-1.06), 0.023]]. A CD4 cell count lower than < 200 per mm(3) [1.67 (0.99-2.81), 0.053] and HCV genotype 4 [0.66 (0.42-1.02), 0.066] were marginally associated with LS ≥ 9 kPa. In conclusion, the prevalence of cirrhosis in HIV/HCV-coinfected patients seems to be higher than previously reported in studies based on liver biopsy. Older age, alcohol consumption and lower CD4 cell counts are related with significant fibrosis. The latter association supports an earlier starting of antiretroviral therapy in this setting.