Application of geogrids can be economical yet technically and environmentally compatible solution to traditional methods of improving pavement bearing capacity. Today, wide range of geogrid products is available in the market. Available products vary in manufacturing technique, aperture size and shape, tensile properties etc. When selecting the geogrid for a specific project most contractors consider aperture size and tensile strength and more recently new the radial secant stiffness ratio at low strain. Calculation of radial secant stiffness ratio requires determination of tensile strength in minimum of four directions. Introduction of new testing directions demands adjusting test procedure which is traditionally carried out in accordance with HRN EN ISO 10319. In this masters thesis test methods for determination of tensile properties are described. A new procedure for testing biaxial geogrids has been established by modifying the HRN EN ISO 10319 standard regarding the specifics of multidirectional testing. According to the established procedure, tensile properties were tested on two biaxial geogrids produced by the welding process for seven test directions (0 °, 15 °, 30 °, 45 °, 60 °, 75 ° and 90 °).