The Raman spectrum of yellow Hg2I2 contains features at 110 and 192 cm-l assignable to Hg-Hg stretching and Hg-1 stretching respectively. The spectrum of yellow HgI2 at c. 150� shows bands at 33 cm-1 (I-Hg-1 bending) and 133 cm-1 (Hg-I stretching). The Raman shifts for red HgI2 are 24, 111, and 137 cm-l, attributable to I-Hg-1 bending, symmetric and asymmetric Hg-1 stretching respectively. Assignments are made on the basis of factor group analyses on the Bravais unit cells. Some force constants are calculated.