马氏管全称马尔比基氏小管（英语：Malpighian tubule system），是常见于节肢动物（如昆虫纲、多足纲、蛛形纲）及部份缓步动物（水熊虫）等“泛节肢动物”（Panarthropoda）的排泄和渗透调节的主要器官，帮助他们保持水和电解液平衡。以发现者意大利解剖学家马尔比基（Marcello Malpighi）命名。

马氏管位于消化道中后肠交界处，为细长之管状物，由一层细胞组成；其基端开口于中肠和后肠的交界处，盲端封闭游离于血腔内的血淋巴中。介壳虫仅仅有两个马氏管，而蝗虫的大的种类可能有到200个马氏管；蚜虫是唯一没有马氏管的昆虫。

The Malpighian tubule system is a type of excretory and osmoregulatory system found in some insects, myriapods, arachnids, and tardigrades.

The system consists of branching tubules extending from the alimentary canal that absorbs solutes, water, and wastes from the surrounding hemolymph. The wastes then are released from the organism in the form of solid nitrogenous compounds. The system is named after Marcello Malpighi, a seventeenth-century anatomist.