Lapsang souchong (often shortened to simply "lapsang") is a black tea from Fujian province in China. Called 正山小种 (in Pinyin, zheng1 shan1 xiao3 zhong3) or 烟小种 (yan1 xiao3 zhong3) in Mandarin, this tea is considered to be one of the most strongly-flavored teas. It was historically considered a "man's tea", but recently has become popular with women as well as men.

Souchong is a grade of fine Chinese tea typically oxidised for a very long time, even by the standards of black teas. The Lapsang souchong is a souchong tea which has been withered over pine or cedar fires, pan-fried, rolled and oxidised before being fully dried in bamboo baskets over burning pine. The result is a flavor usually described as "smoky". Sometimes, the flavor is described as "oakey", a reference to fine wine (which are stored in oak barrels and develop a detectable flavor) but, in fact, oak is not used in the process.

Tea drinkers describe lapsang's flavor as "assertive" and "bold". Lapsang souchong is considered most complementary to spicy or salty foods. Also, it is purported that this tea is well-suited to outdoor enthusiasts, especially after intense physical activities like hiking, distance running, or rock-climbing.

Some people who try lapsang souchong have negative reactions to its flavour and aroma. It can be bitter, and is certainly not sweet. Lapsang souchong is described sometimes as an "acquired taste", or a substance one must taste several times before liking the taste.

Some tea connoisseurs compare the taste of low-quality lapsang souchong to that of cigarette ashes.

Trace amounts of lapsang souchong are included in the Twinings company's Earl Grey blend.