[Purpose] This study was aimed to investigate the effects of Ergon® IASTM applications on the upper or lower part of the Superficial Back Line (SBL) on the hamstring's flexibility. [Participants and Methods] Sixty University students (age=24.4 ± 4.39; height=176.78 ± 8.31 cm; weight=75.16 ± 11.21 kg) were randomly divided into three sub-groups and received a single 15-minute treatment with Ergon® Technique in a) the upper and b) the lower part of SBL or c) served as control. The participants received one treatment per week for four weeks with a simultaneous pre-and post-therapy assessment of their hamstrings flexibility using the passive Straight Leg Raising (SLR). [Results] Both experimental groups improved SLR performance from pre to post during the four weeks from 4.4% to 9.2% in the trunk group and from 4.9% to 8.0% in the lower body group. These differences were significantly greater from the CTRL group. No differences were observed between the two experimental groups. [Conclusion] In conclusion, application of Ergon Technique of either the upper or lower part of the SBL may lead to a significant increase in the hamstring flexibility irrespective of the site of application.