爱华网概率论中，样本空间是一个实验或随机试验所有可能结果的集合，通常用S,Ω,U来表示。例如，如果抛掷一枚硬币，那么样本空间就是集合{正面，反面}。如果投掷一个骰子，那么样本空间就是{1,2,3,4,5,6}。样本空间的任何一个子集都被称为一个事件。如果一个子集只有一个元素，那这个子集被称为基本事件。
有些实验有2个或多个可能的样本空间。例如，从52张扑克牌中随机抽出一张，一个可能的样本空间是数字（A到K），另外一个可能的样本空间是花色（黑桃，红桃，梅花，方块）。如果要完整的描述一张牌，就需要同时给出数字和花色，这时的样本空间可以通过构建上述两个样本空间的笛卡儿乘积来得到。
In probabilitytheory, the sample space or universal samplespace, often denoted S, Ω, or U (for "universe"),of an experimentor random trial is the setof all possible outcomes. For example, if the experiment is tossinga coin, the sample space is the set {head, tail}. For tossing asingle six-sided die, the sample space is {1, 2, 3, 4, 5,6}[1].For some kinds of experiments, there may be two or more plausiblesample spaces available. For example, when drawing a card from astandard deck of 52 playing cards, onepossibility for the sample space could be the rank (Ace throughKing), while another could be the suit (clubs,diamonds, hearts, or spades).
