____________________________________________________________________________________________ Within this paper, basic mechanical properties have been experimentally determined on twelve layers glass fabric-reinforced polyester resin specimens subjected to tensile loads on weft direction until break. Glass fabric of type RT300 (300 g/m 2 specific weight) has been used to reinforce Polylite 440-M888 polyester resin. From a cured composite laminate plate, fifteen specimens have been cut on weft direction using a diamond powder mill to avoid introducing supplementary internal stresses in the laminate. Eight specimens have been tested with 1 mm/min test speed and seven have been tested with 2 mm/min test speed. Young's modulus, tensile strength, load at maximum load, extension at maximum load and other important features have been experimentally determined on a " LS100 Plus " Lloyd Instruments materials testing machine using Nexygen software.