开放世界（英语：open world）是电子游戏关卡设计的一种，在其中玩家可自由地在一个虚拟世界中漫游，并可自由选择完成游戏任务的时间点和方式。这类型的游戏也常被称为「漫游式游戏」（free roam）或着，被不严谨地称呼为「沙盒式游戏」（sandbox），「开放世界」和「漫游」代表了游戏中不存在人为的阻碍，没有线性关卡设计中常见的隐形墙和读取画面。开放世界游戏并不一定是沙盒式游戏，在真正的沙盒式游戏中，玩者可自由对游戏世界进行修改，并创造自己的游玩方式。 通常来说，开放世界游戏依然在游戏环境中有着一定的限制，这可能是由于无法克服的技术限制，或是游戏线性架构中刻意安排（例如锁住无法前往的区域）。

Open world is a term for video games where a player can move freely through a virtual world and is given considerable freedom in regards to how or when to approach objectives, as opposed to other computer games that have a more linear structure to its gameplay. Open world and free-roaming suggest the absence of artificial barriers, in contrast to the invisible walls and loading screens that are common in linear level designs. Generally, open world games still enforce many restrictions in the game environment, either because of absolute technical limitations or in-game limitations (such as locked areas) imposed by a game's linearity. Examples of high level of autonomy in computer games can be found in MMORPG or in other games adhering to the "open world concept". Their main appeal is they provide a simulated reality and allow players to develop their character and its behavior in the direction of their choosing. In these cases, there is often no concrete goal or end to the game. There are limitations to this autonomy through the rules of the simulation and its limitations. But the direction of gameplay may or may not rely ultimately upon the decision of the player, as in some cases this can be completely controllable by the player, the type depends on the requirements and availabilities of the game.