Many differences between Pac-Man and Mouse Trap are aesthetic: the dots become cheese, the player is a mouse, the ghosts are cats, and power pills are bones that turn the player into a dog.

The gameplay of Mouse Trap differs from that of Pac-Man in the following ways:

• The player can open and close the yellow, red, and blue sets of doors at the press of a matching colored button.
• The player can store dog bones for later use at his or her discretion by pressing a fourth button — a large round "Doggie Button" with a picture of the dog's head on it.
• The four ghosts are replaced by six cats, worth 100 points for the first cat eaten, 300 for the second, 500 for the third, 700 for the fourth, and 900 for the fifth and subsequent cats. Point values reset when another bone is used. Each cat eaten spawns a slightly faster replacement.
• A seventh monster, a hawk, will eat both mouse and dog. Only the mid-screen "IN" field stops the hawk, by causing it to move randomly instead of chasing the player, but this will beam the mouse into one of the four corners.
• Bonus point prizes do not appear at intervals, but are constantly available. Eating one triggers the next in the series to appear. Point values start at 1000 for the first prize and increase by 200 for each subsequent prize, with the last prize being worth 7200 points. When the last prize is eaten or the player loses a life, the sequence restarts. There are thirty-two in all: a wedge of Swiss cheese, a paperclip, a safety pin, a key, an apple, a trophy, a candlestick, a pair of scissors, a pair of pliers, a pair of eyeglasses, a clock, a bottle, a gem, a bugle, a screw, a hammer, a diamond ring, a light bulb, a sewing needle, a fork, a thimble, a knife, a cocktail glass, a fishbone, a pear, a peanut, a die, a telephone handset, a die with "C A F" on the faces, a spool of thread, a teacup, and a pistol.
• There is a 10,000 point bonus for clearing the board of all cheese. A player who ends a stage as a dog will begin the next stage in that form.

Coleco ported Mouse Trap to its own ColecoVision console, with 15 prizes instead of 32, an option to leave the hawk out, and different sound effects. Coleco's Intellivision port adds an audio warning when a cat is about to enter the maze, but suffers from blocky graphics. The score differs: 90 points for each cheese, cats are 100, 300, 500, 700, 900 and 1100 points worth.

Coleco also ported Mouse Trap to the Atari 2600, simplifying graphics and gameplay. The maze is more squat with brighter walls, and doors form a single colored set that flickers. Gameplay basics are the same, but the hawk, the "IN" area, and the bonus prizes are missing, there are three cats instead of six, and all doors move at once. Scoring is also reduced significantly: cheese is worth 1 point instead of 10 points, cats are worth 10 points and do not increase in value, and clearing a maze awards only 100 points.

In 1982, Buckner & Garcia recorded the song "Mousetrap" using sound effects from the game, and released it on the album Pac-Man Fever. When they rerecorded the album in 1999, they were unable to find a machine and used sounds from nature, instead.

• Lady Bug
• Heiankyo Alien