Nintendogs is a realtime pet simulation video game developed and published by Nintendo for the Nintendo DS handheld video game console. It was first released in Japan, and was later released in North America, Australia, Europe, and other regions. It was originally released in three different versions: Dachshund & Friends, Lab & Friends (Shiba & Friends in Japan), and Chihuahua & Friends. It has been re-released twice since then, first as a bundled release with a special edition Nintendo DS with a new version called Nintendogs: Best Friends, and then later as Nintendogs: Dalmatian & Friends.

Nintendogs uses the DS's touchscreen and built-in microphone. The touch screen allows the player to pet a dog, as well as to use various items that can be found or purchased. These range from balls and frisbees, to toys, to grooming supplies to keep the dogs happy. The microphone is used to call to the player's dog by speaking the name given to the dog in the beginning of the game as well as to teach the dog tricks such as "sit" or "roll over". Players can bring their dogs on walks and to the park if they so choose. They may interact with other players in multi-player by using the DS's wireless linkup. It also uses the DS's internal clock and calendar to allow the dog to grow hungrier or dirtier based on the elapsed time.

Nintendogs received critical acclaim. It has an aggregate score of 85% at Game Rankings, and has won many awards, including the 2006 Innovation Award from PC World and Best Handheld Game from the Associated Press. As of March 31, 2015, all versions of Nintendogs combined have sold 23.96 million copies worldwide, making it second on the Nintendo DS best-sellers list, behind only New Super Mario Bros. Because of Nintendogs' success, Nintendo has made several related products, including Nintendogs toys and a series of Nintendogs trading cards. At E3 2010, it was announced a sequel, titled Nintendogs + Cats, would be released for the Nintendo 3DS.