Number of laboratory studies; have shown that geosynthetics reinforcement improves the performance of flexible pavement either by ex-tending the service life or by savings in base course thickness. In spite of the good laboratory evidence for the geosynthetics reinforced flexible pavement, the mechanism that enables and governs the reinforcement function is still unclear [1]. Cyclic laboratory test has been one of the ways, used for assessing/evaluating the soil-geosynthetic interaction mechanisms. In such a tests contribution of geosynthetics prop-erties, interface shear provided by geotextiles and interlocking provided by geogrids when used under or within the base course of flexible pavement are mainly concentrated. This paper reviews literature of laboratory model studies carried out by various researchers over the globe. This review indicates that, appreciable improvement due to geosynthetics reinforcement depends upon various factors viz. location of geosynthetics, geogrid aperture size, geosynthetics properties, mainly stiffness, variation of base course thickness and strength of subgrade soil. The findings of these laboratory studies are also correlated with the same nature of field studies finding.