In this paper, investigations on reinforced soil utilizing Discrete Element Method (DEM) modelling are presented. A three dimensional (3D) Discrete Element model is constituted to evaluate displacements and contact forces between discrete particles in the reinforced soil structure. The granular soil particles and the discrete geogrid reinforcement have been modelled “Computer Aided Designed” (CAD). The mesoscopic load transfer mechanism of the reinforced (RE) soil element has been evaluated. Arching effects have occurred randomly between the granular soil particles and the discrete geogrid. Those arching effects have led to local stress concentrations between the particles and to high tensile forces in the geogrid at certain places. Moreover, three soil geogrid interaction effects have been determined. When the discrete clumps have entered the gaps of the discrete geogrid, the longitudinal and transverse members of the reinforcement have been pushed side wards. This effect has been classified as interlocking effect. While loading the soil element, grains have entered between the single strings of the longitudinal and transverse members of the reinforcement. This effect has been defined as single string interaction effect. In longitudinal but also in transverse direction the geogrid has aligned to the surrounding granular particles. This so called alignment effect has led to a permanent contact between geogrid and soil particles resulting in interfriction effects.