深喉（Deep Throat）是在人类性行为过程中，性伴侣将整个勃起的阴茎吞入口腔、通过会厌，直向咽喉，是为男性阴茎口交的一种类型。但阴茎长度必须够长才能深喉。一般以口行动者为主控者，而通常指男性（阴茎被吞）者为被施行者。

此行为绝大多数人难以进行，原因是当软颚被接触时会引起人体自然的呕吐反射。不同的人对此有不同的敏感度，有的人或可逐渐适应。 与一般为男性阴茎口交相比，舌不动而无法吸吮，而阴茎头被性伴侣的咽喉紧密接触而受刺激。

此行为少数出现在欧美色情片中，亚洲并不多见。

Deep-throating is a sexual act in which a person takes their partner's entire erect penis deep into their own mouth and into the throat. The practice is a type of fellatio when the giving partner is in control, while deep throat penetration by an actively thrusting partner is called irrumatio; both are a form of oral sex. For deep-throating, the penis has to be long enough so that it can reach the back of the recipient's throat. The person whose penis is inserted is usually referred to as the receiving partner, and the person who performs deep-throating is referred to as the giving partner. The technique and term were popularized by the 1972 pornographic film Deep Throat.