The Juventus forward has now scored 93 international goals, 16 behind Iran legend Ali Daei’s world record. He scored an early penalty, before Vytautas Andriuskevicius equalised.
Then Ronaldo’s 20-yard shot went in off the head of Lithuania goalkeeper Ernestas Setkus and he scored two more from Bernardo Silva passes, before William Carvalho’s injury-time fifth.
Tonight’s result keeps Portugal in an automatic qualifying place, five points behind Group B leaders Ukraine. It was an eighth international hat-trick for 34-year-old Ronaldo, who also scored four against in Andorra in 2016.