Background: Neuromobilization (NM) includes neurophysiological parameters that vary between clinicians. This randomized controlled trial aimed to investigate the NM on the outcomes of participants with shoulder impingement syndrome (SIS) following treatment sessions (base line to follow up). Study design: Single blinded randomized control clinical trial. Methods: Patients (80) with shoulder impingement syndrome (SIS) were asked to participate in this trial. At the first session, participants were randomly assigned to either control group (40) or experimental group (40). After the baseline assessment routine physiotherapy was executed for both groups, while NM was provided to experimental group. Pain and functional disability score were evaluated on baseline, post treatment and after follow up. Pain was considered as primary out come and functional disability score as secondary outcome. Improvement was evaluated at post treatment and follow up. Differences in outcome between groups were evaluated with clinical improvement. Results: The experimental group compared with control group at 11th week had lower mean pain score 2.15(1.66-2.64) vs 4.90(4.41-5.40); between group difference, 1.82; 95% (CI), -2.38 to -1.25; P ˂ 0.001 and Partial ƞ2=0.33, similarly functional disability score 28.58(27.32-29.83) vs 20.10(18.84-21.36); between group difference ,5.62; 95%CI,(4.32-6.92); P˂ 0.001 and Partial ƞ2=0.49. Over all pain and functional disability score were improved among experimental group relative to control group at 11th week. Conclusion: In an experimental setting, the delivery of neuromobilization leads to significantly different outcomes in participants than in control group. Studies are still required to explore the mechanisms underlying neuromobilization effects. Trial registration: IRCT20190121042445N1, Registered 19 February 2019. Key words: shoulder impingement, neuromobilization, functional disability.