On studying newly received material of Haplolobus, mostly from New Guinea, the key in Husson & Lam 1953 ¹) proved to be far from satisfactory in several respects. This is why all material now available has been given a critical consideration or reconsideration, as the case may be, and from this originated a new revision with a new key, which is presented here. Since the flowers of the various Haplolobus species are of the same type and very uniform, and since they are wanting in so many specimens either in one of the sexes or in both, it appeared, for the time being at least, unfeasible to use them for differential characteristics in the key. The same holds true for the fruits. Only when abundant flowering and fruiting material will be available is there a chance (but no certainty) that good differential characters will be detected in flowers and (or) fruits.