Methods: A retrospective cross-sectional study involving patients with HBcIgM positivity between June 2006-December 2007, satisfying the definition for AHB and CHBF,and fulfilling the exclusion criteria was performed. HBcIgM test were done by using Microparticle Enzyme Immunoassay (MEIA) and results were expressed as an Index value.HBcIgM positivity was defined as Index value of >1.00 Results: 74 patients were positive for HBcIgM and 60 fulfilled the criteria(33 AHB, 27 CHBF).HBcIgM was significantly higher in AHB compared with CHBF(median 3.46 vs 1.70;p <000.5).The HBcIgM arbitary Index value of 2.76 was highly sensitive(97%) and specific(85%) in diagnosing AHB with high accuracy(AUROC 0.964;95% CI:0.925-1.003;p<0.0005).Among patients in both groups, there was a weak, but significant negative correlation between HBcIgM and PT above control(r = -0.309,p =0.016).However, among patients with CHBF,the negative correlation between HBcIgM and PT above control was moderately strong(r = -0.557,p =0.003).There was also a weak, but significant positive correlation between HBcIgM and albumin in with CHBF(r = +0.434,p =0.024).