Purpose: Flexor injuries are most common in the hand and require special attention and experience from the surgeon. Both quality and technique affect the stability of the suture. The selection of the optimum method will influence the process of rehabilitation. The aim of this study was to compare three different suture techniques based on the strength, depending on the method of breakage, i.e., axial or pulley load. Methods: The study was divided into six sessions. The research material was dissected deep flexor porcine tendons. Three types of stitches were used: the modified Kessler suture with an additional running suture, the cruciate four-strand suture with an additional running suture and the multistrand running suture. We obtained 120 sutures, 40 for each technique. Breaking strength was assessed using a tensile machine in two ways, i.e., axial or pulley load, with 20 sutures per group. Results: The strongest suture for both axial and pulley load was the cruciate four-strand suture. Between the multistrand running suture and the modified Kessler suture, there was no statistically significant difference in the strength of breaking for both axial and pulley load. Comparing the two ways of breaking, there was no statistically significant difference in the strength of the suture. Conclusions: The multistrand running locking suture is a good alternative to widely used core sutures. It not only provides the same strength as other techniques examined by us but also reduces the procedure time and trauma to the tips of the tendon.