This systematic review aimed to assess if topical application of hyaluronic acid (HA) reduced complication rates after mandibular third molar (M3) surgery. PubMed, CENTRAL, Embase, and Web of Science were searched for randomized controlled trials (RCTs) assessing the efficacy of topical hyaluronic acid for mandibular third molar surgery. Gray literature was also searched. 12 RCTs were included. Meta-analysis showed that pain scores were significantly reduced after M3 surgery with the use of HA on the 1st, 2nd/3rd, and 7th postoperative days. Using postoperative maximal mouth opening (MMO) data, we noted that MMO was significantly better in the HA group on the 2/3rd post-operative day but not on the 7th postoperative day. Meta-analysis of just three studies showed that swelling was significantly reduced on the 1st postoperative day with the use of HA, however, no such difference was noted on the 2nd/3rd and 7th postoperative days. Alveolitis and infection data were not reported by the majority of studies which precluded a meta-analysis. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) certainty of evidence was low to moderate. Low-moderate quality of evidence suggests that topical application of HA may reduce pain as well as early trismus and swelling in patients undergoing M3 surgeries. The effect size of pain reduction is small thereby raising questions about its clinical significance. High inter-study heterogeneity and low-quality of trials are significant limitations. High-quality RCTs are needed to generate quality evidence.