黑胡椒（学名：Piper nigrum，英文：black pepper），又名黑川，是胡椒科的一种开花藤本植物，它的果实在晒干后通常可作为香料和调味料使用。同样的果实还是白胡椒、红胡椒与绿胡椒的制作原料。黑胡椒原产于南印度，在当地和其他热带地区都有着广泛的种植。黑胡椒的果实在熟透时会呈现黑红色，并包含一粒种子；果实在晒干后会成为直径5毫米的胡椒子核果。

干燥的黑胡椒粉是欧洲风格菜肴的常用香料，自古以来，黑胡椒就因其在调味与医学上的双重价值而备受珍视。黑胡椒的香馥来自其含有的胡椒碱。常简称作“胡椒”的黑胡椒粉，是全世界使用最广泛的香料之一，在世界各地的餐桌上都可见到，通常会与精制食盐放在一起。

Black pepper (Piper nigrum) is a flowering vine in the family Piperaceae, cultivated for its fruit, which is usually dried and used as a spice and seasoning. When dried, the fruit is known as a peppercorn. When fresh and fully mature, it is approximately 5 millimetres (0.20 in) in diameter, dark red, and, like all drupes, contains a single seed. Peppercorns, and the ground pepper derived from them, may be described simply as pepper, or more precisely as black pepper (cooked and dried unripe fruit), green pepper (dried unripe fruit) and white pepper (ripe fruit seeds).