The Nintendo Network was an online service run by Nintendo that provided free online functionalities for the Nintendo 3DS and Wii U systems and their compatible games. Launched in 2012, it was Nintendo's second online service after Nintendo Wi-Fi Connection; the Nintendo Network was not a component of the Nintendo Switch, which uses the subscription based Nintendo Switch Online, although Nintendo Network IDs were able to be linked to the Switch via Nintendo Accounts.

The service was shut down by Nintendo on April 8, 2024, leading to functions such as online play, global leaderboards, SpotPass, and most other online features of both the Wii U and 3DS no longer being accessible; the only services which remain online are Pokémon Bank and Poké Transporter, system software and game updates, the 3DS theme shop, and re-downloading previously purchased software from the Nintendo eShop for their respective systems.

On January 20, 2012, an image of Theatrhythm Final Fantasy's box art was released showing a "Nintendo Network" icon in the corner of the box. It was speculated that "Nintendo Network" was a rebranding of the Nintendo Wi-Fi Connection.

Nintendo officially announced Nintendo Network on January 26, 2012. Nintendo stated that Nintendo Network would be an entirely new unified network system as opposed to a rebranding of Nintendo Wi-Fi Connection. Nintendo stated that the Nintendo Network would provide the infrastructure for online multiplayer (through universal friend codes on the Nintendo 3DS and a user account system on the Wii U), SpotPass, and the Nintendo eShop. During the Pre-E3 Nintendo Direct, Nintendo clarified that Nintendo Network would be the basis for Nintendo's new social network known as Miiverse. Nintendo Network would provide the network infrastructure for the Nintendo 3DS, for the Wii U, and was initially planned for future Nintendo platforms.

Former president of Nintendo Satoru Iwata said, "Unlike Nintendo Wi-Fi Connection, which has been focused upon specific functionalities and concepts, we are aiming to establish a platform where various services available through the network for our consumers shall be connected via Nintendo Network service so that the company can make comprehensive proposals to consumers."

On October 4, 2023, Nintendo announced the discontinuation of the Nintendo Network service for the Wii U and Nintendo 3DS by April 2024, which would shutdown online play features and SpotPass. On January 23, 2024, Nintendo announced that the service would specifically shut down at 00:00 UTC on April 9, 2024. The servers were shut down at 02:00 UTC on that day. Some online services, such as Pokémon Bank and Poké Transporter and third-party games not using Nintendo Network continue to function, however they may also end in the future.

Some features of the Nintendo Network had shut down earlier. Nintendo TVii in North America shut down on August 11, 2015. Miiverse, Wii U Chat, and Nintendo TVii in Japan had shut down on November 7, 2017. Most of the official streaming services are no longer accessible on the 3DS and Wii U, and the Nintendo eShop for these systems closed on March 27, 2023. Previously purchased content from the Nintendo eShop remains re-downloadable, and will remain so for the foreseeable future. The ability to merge funds that were left on the Nintendo Network ID to a Nintendo Account ended on March 11, 2024.

After the shutdown, users that were still connected to the service were able to continue playing post-closure if their consoles remained on, with some continuing to play for over a month after the service's intended shutdown. The final player stayed on for several months after the shutdown, finally disconnecting on November 4, 2024. Since the shutdown, there have been fan-made attempts to restore the functionality of the Nintendo Network, with the most popular one being Pretendo Network. It can be accessed with custom firmware on the Nintendo 3DS family, and either custom firmware or SSL bypassing on Wii U.