The knowledge of knotting techniques on yarns with complex constructions is extremely important in a series of activities. One such activity is the scouting, towards which this master's thesis is focused. In the introductory part of the master's thesis is given a review of the types of yarns related to the formation of scout knots. The main objective of the master's thesis is to examine the tensile properties of yarns that are tied to various scouting knots and furhrermore, to determine which knot is more appropriate for the use regarding the values. The tensile properties of yarn tied to different types of scouting knots were tested separately on dry samples, wet samples (to simulate the use of yarn in seawater), samples that passed the process of abrasion with a certain number of cycles and samples aged in seawater. On the basis of the measurements, it was found that the breaking elongation is the highest for the yarn tied to granny knot, and fishing knot. For samples aged in seawater, the same was observed for a double overhand knot. For samples tested in the water, the highest values of braking force has fishing knot, which is easily bonded and provides great safety in application. The lowest values of the breaking elongation in all three conditions was measured for the yarn with bowline knot. When comparing the tensile properties of cotton and viscose yarn, it was shown, in both tests, that one of the samples with the highest values of the breaking elongation is double overhand knot. As far as the braking force is concerned, in all three conditions, and for both yarns used, the highest value is observed for the yarn tied to granny knot. The lowest value was measured for the yarn with bowline knot. By simulating the use of yarns in nature using abrasion device, it is found that all values are significantly reduced by increasing the number of cycles (starting at 100 and increasing by the next 100 cycles). The importance of the examination is evident in the fact that knowledge about the tensile properties of the underlying samples is essential for the preservation of personal and general safety of the persons who use them.