选择性5-羟色胺再摄取抑制剂（英语：Selective Serotonin Reuptake Inhibitors）(SSRI)，也称选择性血清素再摄取抑制剂，是一类常用的抗抑郁药，用来治疗抑郁症、焦虑症、强迫症及神经性厌食症。

已知5-羟色胺在控制情绪时发挥着重要的作用，SSRI的作用机制是通过抑制突触再摄取泵对神经递质5-羟色胺的再摄取以增加突触间隙中5-羟色胺浓度，SSRI对肾上腺素能受体(α1，α2，β)、胆碱能受体、GABA受体、多巴胺能受体、组胺受体、5-羟色胺能受体（5HT1A， 5HT1B， 5HT2）或 GABA_AR没有明显的亲和力。

Selective serotonin re-uptake inhibitors or serotonin-specific reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder and anxiety disorders.

The exact mechanism of SSRIs is unknown. SSRIs are believed to increase the extracellular level of the neurotransmitter serotonin by limiting its reabsorption into the presynaptic cell, increasing the level of serotonin in the synaptic cleft available to bind to the postsynaptic receptor. They have varying degrees of selectivity for the other monoamine transporters, with pure SSRIs having only weak affinity for the norepinephrine and dopamine transporters.