Measurements were made of Faraday rotation on ∼1‐&mgr;‐thick evaporated and recrystallized, polycrystalline InSb films. The experiments were carried out at room temperature using a microwave bridge circuit and a trimode turnstile as a polarimeter. The relative amplitudes and phases of the transmitted electric‐field components were determined with the film placed transversely across a circular waveguide section (TE11mode). Rotations of 30° to 40° were observed for a field of 2 kOe. The results are interpreted in terms of a theoretical model based on free‐carrier Faraday rotation including multiple reflections assuming plane‐wave propagation. The experimental data is in good quantitive agreement with the model forH<1.5 kOe and in qualitative agreement for higher fields.