One or two players take on the role of Bub and Bob, two cute dinosaurs who must battle through 100 platform-packed single screen levels to rescue their girlfriends. Bub and Bob are armed only with the ability to blow bubbles, in which the game's many enemies can be trapped and killed. The bubbles can also be used as temporary platforms, to help the dinosaurs reach previously inaccessible areas of a level.

Any trapped enemies who are not killed quickly enough will turn red and escape their bubble prison. These angry enemies are much faster than before, making them harder to kill. Enemies also become angry if players are taking too long to complete a level. Defeated enemies are turned into bonus fruit items that can be collected for points.

On many levels, bubbles containing fire, water or a lightning bolt appear. These can be burst by players to release their contents and destroy enemies. The fire bubble drops flames down onto the nearest platform, killing any enemies it hits. The lightning bubble sends a lightning bolt horizontally across the screen, its direction dictated by whichever side of the bubble the player hits to burst it. The water bubble releases a torrent of water that will quickly flow down the platforms to the bottom of the screen. Any enemies caught in the flow are killed.

Bubbles containing letters also appear. The aim is to collect the letters needed to speel the word E.X.T.E.N.D. which earns players an extra life.

The game's simple-yet-involving game-play saw Bubble Bobble become an instant classic. Its two-player co-operative mode, coupled with the incredible amount of hidden secrets and potential for strategic play - unheard of in the platform genre - would set the standard by which all other platform games were judged.