Antimycobacterial activity of a series of alkoxybenzoic acids including 4-methoxybenzoic acid (II), 4-ethoxybenzoic acid (III), 4-propoxybenzoic acid (IV), 4-butoxybenzoic acid (V), 4-pentoxybenzoic acid (VI), 4-allyloxybenzoic acid (IX), 4-isopropoxybenzoic acid (VII), 4-isobutoxybenzoic acid (VIII) and 4-benzyloxybenzoic acid (X) has been determined and found to increase with the lipophilicity of the compounds expressed by the corresponding HPLC capacity factors. Also determined were the pKa values of the compounds mentioned. The most active compound, 4-pentoxybenzoic acid (VI), is comparable with commercial antituberculotics when tested in vitro.