在概率与统计相关学科中，爱尔朗分布（Erlang Distribution）是一种连续型概率分布。Erlang分布的译名较多，如爱尔兰分布，埃朗分布，埃尔朗分布，爱尔朗分布，厄朗分布等等；此外在不同学科间，Erlang分布的习惯译法也可能不同。

该分布与指数分布一样多用来表示独立随机事件发生的时间间隔。相比于指数分布，爱尔朗分布能更好地对现实数据进行拟合（更适用于多个串行过程，或无记忆性假设不显着的情况下）。除非退化为指数分布，爱尔朗分布不具有无记忆性（或马尔可夫性质），因此对其进行分析相对困难一些。一般通过将爱尔朗过程分解为多个指数过程的技巧来对爱尔朗分布进行分析。

In probability theory the hypoexponential distribution or the generalized Erlang distribution is a continuous distribution, that has found use in the same fields as the Erlang distribution, such as queueing theory, teletraffic engineering and more generally in stochastic processes. It is called the hypoexponetial distribution as it has a coefficient of variation less than one, compared to the hyper-exponential distribution which has coefficient of variation greater than one and the exponential distribution which has coefficient of variation of one.