A series of 143 salicylanilidessubstituted in positions 4 and 5 and in positions 3′ and 4′ was synthesized. The compounds were evaluated for in vitro antimycobacterial activity against Mycobacterium tuberculosis, Mycobacterium kansasii, and Mycobacterium avium. To describe the structure‐antimycobacterial activity relationships (QSARs), an approach based on the combination of the Free‐Wilson and Hansch