The 31-year-old airline pilot from Dallas, TX popped the question to marketing representative Girardi, who tearfully accepted his proposal after beating fellow finalist Tenley Molzahn on tonight's episode.
The episode featured Pavelka introducing both Girardi and Molzahn to his family, who arrived on the Caribbean island of St Lucia to help him make his choice.
Both couples also went on one last date before the final Rose Ceremony, with Pavelka treating Vienna to a steamy mud bath in a volcanic sulphur spring, and enjoying a yacht ride and snorkelling in the coral reefs of St Lucia with Tenley.
Show host Chris Harrison had previously promised that the show had "one of the most beautiful" endings in the series history.
The Bachelor airs on ABC.