Paulo Fonseca's side produced a solid second-half display to earn all three points after finding themselves level at the break in Vila do Conde.
Maicon had put Porto ahead in the sixth minute only for Edimar Fraga to equalise midway through the half.
But Porto flew out of the blocks after the interval and restored their lead as top scorer Jackson Martinez hit his 11th league goal of the season six minutes into the second period.
Danilo sealed the win late on for the defending champions, who dominated possession to record their second Primeira Liga victory in a row.
Benfica, meanwhile, had to come from behind twice in the first half against struggling Olhanense before they were finally able to seal a 3-2 victory and remain level on points with Porto.
Femi Balogun opened the scoring after seven minutes, but Lima soon levelled for Jorge Jesus' side.
Paulo Regula put Olhanense back ahead just after the half-hour mark, but again Benfica fought back as Nemanja Matic fired home in the 37th minute.
Jesus introduced Miralem Sulejmani at the break and the Serbian striker made an immediate impact as he scored in the second minute of the half to condemn Olhanense to their fourth straight league defeat.
In Sunday's other fixture, Vitoria Guimaraes extended their unbeaten league run to three games with a comfortable 2-0 victory over third-bottom Arouca.
Tomane broke the deadlock in the 28th minute with his second goal of the season, before Leonel Olimpio sealed the victory before half-time with a 41st-minute penalty.
