堆肥式厕所（英语：composting toilet）是一种以极少水量冲厕或甚至是无水的厕所，排泄物流入便池中混合木糠、椰棕或泥炭藓等物质带氧分解成堆肥。堆肥式厕所主要应用于缺乏供水及集体排污系统的地方以取代传统的冲水式厕所，又或者是方便将人类排泄物循环再做成肥料使用，主要对非食用植物施肥。堆肥式公厕在瑞典许多的公路旁及英美的国家公园得到广泛应用。排泄物混合的额外物质有助分解、吸水及减少臭味挥发，分解的速度亦比传统厌氧分解的化粪池要高。

A composting toilet is a type of dry toilet that uses a predominantly aerobic processing system to treat human excreta, by composting or managed aerobic decomposition. These toilets generally use little to no water and may be used as an alternative to flush toilets. They have found use in situations where no suitable water supply or sewer system and sewage treatment plant is available to capture the nutrients in human excreta. They are in use in many roadside facilities and national parks in Sweden, Canada, US, UK and Australia. They are used in rural holiday homes in Sweden and Finland.