In the present paper a set of 75 coal samples in the ASTM ranking range of anthracite to lignite from different countries have been used to obtain correlations between helium density (HDdmmf) and compositional parameters in terms of WC, O/C and O/H atomic ratios. Based on dry, mineral-matter-free (dmmf) basis helium density is estimated according to the following expression: HDdmmf = 1.5856 - 0.418462 (H/C) + 0.468039 (O/C) + 0.160189 (O/H) HDdmmf = 1.6211 - 0.467168 (H/C) + 0.692099 (O/C) The absolute average percentage errors and correlation coefficients of above two models are found to be 1.30; 0.96 and 1.31; 0.96 respectively. Statistical analysis and comparison of the models with other two earlier models suggest the superiority of present models over earlier one. (C) 2000 Elsevier Science S.A. All rights reserved.