The gameplay in Pac-Man Plus is nearly identical to that of the original Pac-Man. The player controls Pac-Man and attempts to score as many points as possible by eating all the Pac-Dots in the maze, while avoiding the ghosts that roam the maze. Eating a Power Pellet causes the ghosts to turn blue and become vulnerable for a brief period, allowing Pac-Man to eat them for extra points. When the maze has been cleared, a new maze is presented and gameplay continues.
The most noticeable differences between the original game and Plus are various tweaks to the graphics: The maze is green instead of blue, vulnerable ghosts are shortened and have a leaf sticking out of them, the fruits have been replaced by new items (including a can of Coca-Cola), and Blinky is slightly cross-eyed. In addition to these cosmetic changes, Plus also changes the gameplay slightly: Eating an item causes the ghosts to turn both vulnerable and invisible, and doubles their point values while they are vulnerable. Eating a Power Pellet sometimes has unpredictable results, such as turning the maze invisible or turning only three out of all four ghosts blue. The ghosts are also faster and more aggressive than in the original game, making the game seem overall faster-paced and more difficult.