Petrus Olai (disambiguation)

Petrus Olai is a latinization of Peder (Per) Olsson (Olsen) or  Olofsson, used by a number of early modern Scandinavian authors:
 * Petrus Olai (Peder Olsen), ca. 1490–ca. 1570,  Danish Franciscan friar and historiographer
 * Petrus Olai Dalekarlus (1601–1680), Swedish pastor and politician