Objective: The purpose of this pilot study was to evaluate the effects of photobiomodulation (PBM) with a 2940-nm Er:YAG laser on post-operative pain and wound healing at the palatal donor site of subepithelial connective tissue grafts (CTGs). Methods: Ten systemically healthy patients who required CTG surgery completed this randomized clinical trial. Participants were assigned to receive PBM therapy or sham laser treatment of the palate following harvest of the graft. Analgesic consumption was recorded, and a visual analogue scale (VAS) pain questionnaires completed for the first post-operative week. At one week, patients completed an Oral Impact on Daily Performance (OIDP) questionnaire. At one and two weeks, healing was evaluated according to a modified early wound-healing index (MEHI) and the healing index of Landry, Turnbull and Howley (HI). Patients returned at six weeks for assessment of tissue thickness and for collection of a tissue sample. Results: There were no significant differences in VAS scores, analgesic intake, or healing of the palate between the Test and Control groups. The Test group reported more frequent disruptions to doing light work, going out, sleeping, smiling, and interacting with others. Conclusions: Within the limitations of this study, PBM therapy with an Er:YAG laser did not impart any beneficial effects.