The physical and chemical properties of low-and high-sulfur oil shales from 36 deposits throughout the world, and of their retorting products have been investigated and generalized. Barring on the oil qualities, the shales may be divided into three main groups: yielding paraffinic, high-sulfur, and oxygen-compound-rich oils. On the basis of the distribution of sulfur between retorting products, the oil shales from various deposits of the world tested in the standard Fischer assay may be divided into four groups. The first group comprises the oil shales whose retorting yields semicoke containing 100-70 % of the total sulfur (low-sulfur shales). The respective amount of sulfur in semicoke of other shales is 70-50 % (II, transitional group), 50-30 % (III), and 30-20 % (IV), the last two groups comprise high-sulfur shales. Other changes in physical and chemical properties of retorting products may be traced back to be in a good correlation with this feature.