Adalgisel Grimo (died after 634) was a deacon and member of the Austrasian nobility. He is chiefly significant because of his will, dated 30 December 634. This is the oldest known early medieval deed for the territory between the Meuse and the Rhine and contains important information about the settlement, constitutional, economic and social history of this region. A 10th-century transcription of the Latin testament of Adalgisel Grimo resides in the State Archives in Koblenz (Rhineland-Palatinate). The definitive edition of the text was presented in 1932 by Wilhelm Levison.