This paper investigates the design of a high-efficiency bracing system for out-of-plane stability in arches with three ribs. K-bracing system, X-bracing system (with independent configuration or integral configuration crossing the three ribs), and transverse bracing system are typical bracing systems. Utilizing a precise matrix stiffness method (MSM), we established the buckling criterion for three-ribbed arches, with out-of-plane buckling loads determined from eigenvalue analysis. Comparing with transverse bracing system, K-bracing system could achieve better bracing system efficiency for out-of-plane stability. We found that arches with three ribs, equipped with independent K-bracing system, could exhibit higher out-of-plane capacities compared to an arch with integral K-bracing system spanning across three ribs. The reason is that the independent system offers greater restraint to the middle arch rib, thus preventing premature out-of-plane instability. The high-efficiency bracing system is further recommended for arch with three ribs, aiming to maximize the out-of-plane buckling load while minimizing the total material usage.