Mario Power Tennis features variations of tennis matches consisting of characters, courts, and scenarios based on the Mario series. The range of courts includes the standard three types of tennis court, but consists predominantly of those themed upon games in the Mario series, known as "Gimmick" courts. As well as adopting the style aesthetically, these feature thematic elements that influence how the match will be played on that surface, such as the ghosts in the Luigi's Mansion court, which hinder movement when the character comes into physical contact with them.

Although standard tennis is available, variants of the sport can be played which adopt different rules and methods of victory. "Ring Shot" involves the player earning points by hitting the ball through rings of varying sizes, with the number of points dependent on the difficulty of the shot.[9] The player acquires the points whenever a winning shot is made adhering to standard rules; the match is won once the predetermined number of points is equaled or surpassed. A similar mode, "Item Battle", involves the characters using items based on the Mario universe to interfere with each other's game and gain an advantage