Ecliptica - This is an Open World Action survival game, that is written on Qt Quick 3D engine.
qt-nethack - A one of GUI frontend of Nethack, famous rogue-like game. But it is still based on Qt3.
Sudoku — Fancy, feature-complete, cross-platform Sudoku app written in C+/Qt. Includes build+packaging scripts for Windows, Mac OS X and Linux. Originally written for a course at Hasselt University in Belgium.
GNUDoQ - An open source, graphical Su Doku generator and solver with printer support.
Attal : Lords of doom - A themeable turn-based strategy game. But it seems that in-game graphics are drawn by SDL.
Hedgewars - Free Worms-like turn based strategy game. But it use Qt in front-end screen and multiplay lobby screen.
Gottet - A tetris clone. Author made it for his wife.
JAG - An arcade-puzzle 2D game which runs on Linux and Windows. It is free and opensource. 3 in-a-row type game. Uses SDL.
Bubble-chains - Arcade-puzzle game for Windows, Linux. From JAG creators.
PiperWar - non commercial RPG-like game on "paper" with Box2d engine, uses OpenGL (LGPL).
Construqtor - This is educational toy. It allows you to build and control machine in 2D physical world. Uses Box2D for physics simulation, GPC for polygon manipulation and Qt for everything else.
QBoard - A Qt 4.3/4.4 application for playing near-arbitrary board games. It provides a fairly rich interface for setting up and playing such games.
Squaby - Open Source Tower Defense Game for iOS, Android, Symbian, MeeGo, Windows, Mac and Linux. It is part of the example games of the V-Play Game Engine.
Stack With Friends - Open Source physics game with level editor and level sharing feature for iOS, Android, Windows, Mac and Linux. It is part of the example games of the V-Play Game Engine.
Book of Magic - Intellectually challenging puzzle game for Android (commercial). Game is inspired by a brilliant old game Stone Age. Written in Qt/QML/JavaScript.
Worm Shredder - A violent worm action game with different weapons for Android. Both free and paid versions available.
Dead Ascend - An open source, hand-drawn, 2D point'n'click-like escape adventure. Written in mostly Qt/QML and Javascript. For Android and iOS
Tiled - Tiled is a general purpose tile map editor. Originally it was made with Java but now is rewritten using Qt and C+.
Gluon - Gluon is a set of Qt4 based tools and libraries (using openGL, openAL, Box2D and other libraries) designed to make it easy to develop and distribute 2D games over a wide array of target platforms.
Box2D - Box2D is a 2D rigid body simulation library for games. Can be easily integrated with Qt.
Quasi Engine - Quasi Engine is a Qt5 based framework that intends to be a complete multiplatform toolset to ease 2d game development, providing ready-to-use QML elements representing basic game entities needed by most of games. The framework takes the advantage of the new Scene Graph approach on QtQuick 2.0 and uses Box2D for its physics system.
V-Play Game Engine - V-Play is a 2D game engine built on Qt which supports iOS, Android, Symbian, MeeGo, Windows Mac and Linux. Games can be written with Qt & QML/JavaScript with the V-Play gaming components. It features Box2D physics, particles, sprites, multi-resolution and aspect ratio independence, a level editor and native plugins like Facebook or GameCenter. The build server allows to deploy games to iOS & Android easily without the need to install native SDKs.
Bacon2D - Bacon2D is a framework to ease 2D game development, providing ready-to-use QML elements representing basic game entities needed by most of games.
Slate - Slate is a simple pixel art editor written with Qt Quick, available on Windows, Mac and Linux.
Need more?
Linux-Games - Some pure Qt based games can be found there (formerly qt-apps.org).
KDE Games - Various game packages from KDE. It is based on Qt but requires KDE libraries too.
