THE TITLE COMPOUND [SYSTEMATIC NAME: N-methyl-3-(1-naphth-yloxy)-3-(2-thien-yl)propan-1-aminium chloride], C(18)H(20)NOS(+)·Cl(-), was crystallized from 1,4-dioxane. Twofold rotational disorder exhibited by the thio-phene ring in a 0.580 (5):0.420 (5) ratio represents two different conformations of the mol-ecule that exist in the same crystal form. The crystal structure contains strong N-H⋯Cl hydrogen bonds.