载脂蛋白（英语：Apolipoproteins）指那些结合到脂类上的蛋白质（脂溶性物质，如脂肪与胆固醇），他们结合在一起就形成了脂蛋白，后者载着脂类穿梭于淋巴系统与循环系统。

脂蛋白的脂类成分无法溶于水中；然而，因为他们具有如洗涤剂般（两亲性）的特性，载脂蛋白与其他两亲分子（例如磷脂）可以包围着脂类，就制造出了脂蛋白微粒，它自身是水溶性的，并且因此可以被载着穿梭于水相的循环中（如血液、淋巴）。

载脂蛋白也充当酶的辅因子、受体的配体以及脂类转运载体，后者调控脂蛋白的代谢以及他们在组织中的吸收。

Apolipoproteins are proteins that bind lipids (oil-soluble substances such as fat and cholesterol) to form lipoproteins. They transport the lipids through the lymphatic and circulatory systems.

The lipid components of lipoproteins are insoluble in water. However, because of their detergent-like (amphipathic) properties, apolipoproteins and other amphipathic molecules (such as phospholipids) can surround the lipids, creating the lipoprotein particle that is itself water-soluble, and can thus be carried through water-based circulation (i.e., blood, lymph).