Ronaldo scored in the 44th minute, bringing his international goal total to 104. He is five goals short of tying the all-time scoring record for a men’s national team as he enters Euro 2020.
Former Iran striker Ali Daei holds the record, and he is the only other male soccer player to have scored 100 goals.
Portugal, which had a 0-0 tie with Spain in its first warm-up game last week, also got goals from Bruno Fernandes and Joo Cancelo.
Ronaldo had a few golden chances before finally reaching the net at the Jose Alvalade Stadium with a left-footed drive. His goal came two minutes after Fernandes opened the score with a low shot from near the penalty spot.
In stoppage time, Fernandes scored his second goal by hitting the top corner with a shot from outside the area.
Portugal coach Fernando Santos started Fernandes, Bernardo Silva, and Diogo Jota alongside Ronaldo, who was replaced in the 72nd minute. Joo Felix was omitted from the match squad. The defense was headed by Pepe and Rben Dias.
Portugal won its first European title in 2016, defeating host France in the final.