We examined the feasibility of detecting hepatitis C virus (HCV) RNA in formalin-fixed, paraffin-embedded (FFPE) specimens obtained by thin-needle biopsy (TNB). Specimens obtained by large-needle biopsy (LNB) and unfixed frozen tissue served as controls. A total of 23 biopsy specimens, 13 obtained by TNB and 10 by LNB, from 20 patients with chronic hepatitis C were included in the study. HCV RNA was detected by nested reverse transcription-polymerase chain reaction (RT-PCR). HCV RNA was found in FFPE archival specimens obtained by TNB (11 [85%]) or LNB (7 [70%]). The sensitivity was similar in unfixed tissue in which HCV RNA was found in 7 (88%) of 8 TNB specimens and 6 (86%) of 7 LNB specimens. The detection of HCV RNA did not seem to be affected by storage of the paraffin blocks, the presence of advanced fibrosis and cirrhosis, or fragmentation of the core cylinder. TNB yields enough qualitative suitable material to detect HCV RNA by RT-PCR.