Aristolochia bhamoensis from Myanmar is here described and illustrated. This new species is morphologically similar to A. faviogonzalezii (confined to northern Vietnam) and A. cathcartii (growing in the Himalayan region) but is distinguished from the latter two species by having a cream-white upper part of the perianth tube, with visible purple ridges, a trumpet-shaped limb, 5.0-5.5 cm diameter, inner surface of limb lobes densely covered with dark-purple bristles, a nearly circular mouth, 3.2-3.5 cm wide, upper half of throat being dark-purple to blackish, without striations or dots, and lower half purple, with conspicuous white striation. Morphological characters such as a 3-lobed gynostemium and a 3-lobed limb support a placement of the new species in the subgenus Siphisia. A diagnostic key is provided to the seven Siphisia species known from Myanmar.