Numerous meta-analyses have been conducted aiming to compare hyaluronic acid (HA) and placebo in treating knee osteoarthritis (OA). Nevertheless, the conclusions of these meta-analyses are not in consistency. The purpose of the present study was to perform a systematic review of overlapping meta-analyses investigating the efficacy and safety of HA for Knee OA and to provide treatment recommendations through the best evidence. A systematic review was conducted based on the PRISMA guidelines. The meta-analyses and/or systematic reviews that compared HA and placebo for knee OA were identified. AMSTAR instrument was used to evaluate the methodological quality of individual study. The information of heterogeneity within each variable was fetched for the individual studies. Which meta-analyses can provide best evidence was determined according to Jadad algorithm. Twelve meta-analyses met the eligibility requirements. The Jadad decision making tool suggests that the highest quality review should be selected. As a result, a high-quality Cochrane review was included. The present systematic review of overlapping meta-analyses demonstrates that HA is an effective intervention in treating knee OA without increased risk of adverse events. Therefore, the present conclusions may help decision makers interpret and choose among discordant meta-analyses.