What is the life span of the praying mantis? Arah December 10, 2020 00:04 Updated Praying mantises live outdoors for 3-6 months. Related articles Are praying mantises predators? Fun Facts about the Praying Mantis Can I raise butterflies and praying mantises in the same habitat? Do praying mantises fly? How can I tell whether a praying mantis is male or female? Comments 0 comments Please sign in to leave a comment.