胶体渗透压(Oncotic pressure、colloid osmotic pressure、胶体膨胀压、血浆胶体渗透压)，是经由蛋白质所施加之渗透压的一种形态、特别是白蛋白，而在血管中的血浆(血/液体)通常趋向于将水拉入循环系统。胶体渗透压也是相反于毛细管滤过压(capillary filtration pressure)和间质胶体渗透压(Interstitial Colloidal Osmotic Pressure)的一种力量。

Oncotic pressure, or colloid osmotic pressure, is a form of osmotic pressure exerted by proteins, notably albumin, in a blood vessel's plasma (blood/liquid) that usually tends to pull water into the circulatory system. It is the opposing force to hydrostatic pressure. It has a major effect on the glomerular filter pressure.