The defending champions made a strong start to their AFCON campaign with victory over Gambia in their opening match, and it was more of the same in what on paper was their toughest test in Group C.
Ismaila Sarr opened the scoring in the first-half, beating Andre Onana with the help of a deflection, and while Senegal were made to wait for their second goal, it was no surprise when it came with 20 minutes remaining.
Sarr was involved again, playing a lovely ball across the face of goal, and Habib Diallo was on hand at the back post to turn the ball into an empty net as he slid in.
Cameroon's first shot on target did not come until the 83rd minute, but it brought a goal and set up a grandstand finish. A corner was taken short before it eventually was whipped in, and Jean-Charles Castelletto rose well to power a header past Edouard Mendy.
That threatened a nervy finish, as Cameroon for the first time in the match offered a serious threat, and they wasted a massive chance to equalise deep into stoppage-time. Castelletto whipped a brilliant ball into the middle, finding an unmarked Georges-Kevin N'Koudou who somehow headed wide from six-yards out.
The win secured Senegal's place in the last-16, regardless of the result in their final group-stage match against Guinea, and leaves Cameroon with plenty of work to do if they are to avoid a shock early exit.
The Indomitable Lions, who are five-time champions and finished third when hosting the tournament two years ago, sit on just one point from their opening two matches, and will crash out of the tournament unless they beat Gambia in their final group-stage match on Tuesday.