Heinrich von Ahaus (in Dutch Hendrik van Ahuis) (1371–1439) was the founder of the Brethren of the Common Life in Germany.
He was born in 1371, the natural son of Ludolf, Lord of the principality of Ahaus, and Hadwigis of Schöppingen.
About 1396 he joined the Brethren of the Common Life at Deventer, where personal intercourse with the companions of the founder, especially Florentius Radewyns, thoroughly acquainted him with the spirit and methods of the congregation, then in its first fervour.
It is probable that during the plague of 1398 he left Deventer for Amersfort (another Dutch city) with Florentius, on whose death he returned to his native Münster to establish a community there.
Heinrich accompanied Johann Vos van Heusden, Rector of Windesheim, to the Council of Constance (1414–18), where they succeeded in refuting the charges lodged against the Brethren by the Dominican Mathüus Grabow.