Bioconcentration factors (BCF) in fish of organic nonelectrolytes are well correlated by a linear solvation energy relationship (LSER) of the form : log BCF= -0.95 + 4.74 $V_I/100 - 4.39{eta} + 0.88{alpha}$ where $V_I$ is the intrinsic solute molecular volume and ${eta}$ and ${alpha}$ are the solvatochromic parameters that measure hydrogen bond acceptor basicity and donor acidity of the compound. The LSER model can not only correlate the property with an accuracy comparable to molecular connectivity model but also provide a quantitative informationon on the nature and relative strength of solute-target system interactions affecting the property of interest. Such an information can hardly be obtained from molecular connectivity model.