A hot wall technique was applied to grow PbI2thin films of about 100 nm thickness on cleaved surfaces of CdI2single crystals. The band‐edge exciton absorption spectra were investigated for the films grown in various conditions. A very sharp exciton absorption line of 8.8 meV half‐width was obtained in a PbI2single‐crystal film grown at a 75 °C substrate temperature. The sharpness of the exciton line proved the excellent quality of the PbI2film and the usefulness of the technique.