Developments in the field of textile reinforced composites have been increasing in the last several years. In the first developed composite materials, fibers were used as reinforcement element. Textile materials such as staple fibers, bands, filament yarns, cables and two dimensional textiles are widely used as reinforcement elements in composite materials. Spacer fabrics consist of two outer surfaces and a connection layer between those outer surfaces. Spacer fabrics can be classified in the three dimensional textiles. Three dimensional textiles are defined as structures which have three different yarn systems (x,y,z) inside. Thanks to their special characteristics, spacer fabrics show different properties which cannot be met by the conventional textiles. Spacer fabrics can be used in different application areas thanks to their special properties such as three dimensional locations of yarns inside the spacer fabric, application of different materials in the layers and one step production property. The special characteristics of spacer fabrics present different opportunities as a reinforcement material in composite structures. There have been some researches in the literature about the application of spacer fabrics in the composite structures. However these researches are at the beginning stage. In this study, application possibilities of spacer fabrics in composites were investigated. Firstly, the physical properties of spacer fabrics were tested, then composites with spacer fabrics were produced and the properties were tested. As an alternative application, spacer fabrics were used with woven glass fabrics in the composite structure and the mechanical properties were tested. Results of the study showed that spacer fabrics present special advantages in the composite structures as a reinforcement and filler material.