In the PC version of the game, the cook on the ship at the beginning of the game has a full beard; however, in the console versions of the game, he is clean shaven.

During development Michelle had a different face to the release version, as seen in the "Move Up, Ladies" trailer.

Female police officers were originally going to be implemented in the game before being cut. One can be seen in the first trailer for the game.

The Fight Club was originally going to be introduced in The Lost and Damned, but it was cut until The Ballad of Gay Tony. There are still files referencing it in The Lost and Damned.

Originally in The Lost and Damned mission, "Politics", Johnny was supposed to get a uniform to pass by security. This also means that Johnny may have been able to have changed outfits in development.

The second trailer for the game shows that Real Badman didn't originally wear a hat, unlike in the released version.

During development Ilyena Faustin wore different clothes, which can be seen in the second trailer for the game.

Niko's default outfit did not have a white stripe on the collar during development. This can be seen in multiple pre-release screenshots.

The "Vlad Glebov" trailer for the game shows a black variant of the Taxi, which is never seen in the final version.

Both Roman's clothing and hairstyle were changed during development, as seen in a pre-release screenshot.

The third trailer for the game shows that Mikhail Faustin originally had grey hair and a different hair style.

In The Ballad of Gay Tony, there was going to be a completely new vehicle introduced, the Robin, before it was scrapped. The only existence left of it is some handling files.

In The Lost and Damned, there was originally a skate park, but it was cut. You would not use a skateboard, but instead a motorcycle. There are still files hinting at its existence.

In 2010, a lawsuit was filed by Brazilian composer Hamilton Lourenço da Silva with the Civil Court in Barueri against Rockstar Games and Synergex Brazil to restrict trading and distributing of Episodes From Liberty City in Brazil, and Worldwide, due to the song "Conga Kid", which is featured in The Ballad of Gay Tony, having sampled from his song "Bota o Dedinho pro Alto" without his permission. The injunction stated that a fine of R $5,000 (US $3,000) would be issued for each day the expansion was continued to be sold.

Spoiler:After finishing the mission Undertaker, the player finds themselves in front of the grave of the McrReary brother they killed on the previous mission, "Blood Brothers". If the player killed Derrick McReary the they can walk through his gravestone; however, the same doesn't happen with Francis's gravestone, which is solid.

There is an unused variant of the website PeepThatShit.com which refers to Outlook Park as Overlook Park.

In the 2009 edition of The Guinness Book of World Records: Gamer's Edition, Grand Theft Auto IV is credited as the "Largest Voice Cast in a Video Game" with 861 voice actors: 174 individuals voicing the main cast and voice-overs and the remaining 687 were mostly volunteers who wanted to be part of the game in some way.

There were two cut random character missions in The Ballad of Gay Tony. They both involved Luis running into ex-girlfriends. One mission has Luis taking the ex-girlfriend home and defending himself from her brothers, while the other involved the ex planting a bomb in Luis' car. It is unclear if these missions involved the same girlfriend, or two different ones.

The Rhino was originally going to appear in the game, but it was cut. There are still lines of code within The Lost and Damned files that show this.

If the player selects the Uzi while inside a car and then uses the advanced weapons cheat code, Luis will be equipped with the Assault SMG inside the car. Because this was not originally intended, firing the weapon will cause a glitched animation.