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Recent studies of soil landscape relationships in Soodejan region identified clay minerals in calcic, argillic and petrocalcic horizons developed on different landforms. The objectives of this study were: i) to evaluate the versatility of clay minerals in the semi-arid soil environment, and ii) to establish the relationship between the soil properties and types of clay minerals on different landforms. Seven representative pedons on different landscapes were selected for mineralogical study. Physiographically, the study area consists of mountain, hill and plateau. Also, there are flood plain, terraces, summit, back slope, foot slope and small parts of low land that located in the toe slope. The profile was dug on all of the land forms. They were classified as Calcixerepts, Haploxerepts, Haploxeralfs and Haploxerolls with xeric and mesic moisture and temperature regimes. The XRD analysis showed that vermiculite and chlorite minerals had the most extensive extent of the particle-size distribution among the secondary phyllosilicates specially in coarse clay particles. Also there are most of the mixed illite and chlorite minerals in comparison to the other minerals. Presence of triviality amounts of kaolinite in different horizons showed that some minerals are formed under bygone moist continent. In the argillic horizons, smectite proved to be the dominant clay mineral in the fine clay particles and increased by the increasing depth. This matter is in each typic sample. Differences in layer charge with landscape position may be due to differences in weathering processes but the drainage condition caused by topography is a critical factor in the transformation and redistribution of clay minerals.