AbstractPhenylglyoxylic acid (PGA), as a urine metabolite of ethylbenzene and styrene (EB/S), can effectively represent the level of EB/S ingested by the human body through oral inhalation and skin absorption. Compared with measuring EB/S levels directly in the environment, detecting the level of PGA in urine has the advantages of high specificity and noninvasive sampling. In this paper, a metal–organic framework (MOF)‐based sensorZn‐PBA = ({[Zn(PBA)·H2O]·2H2O}n, H2PBA = 4‐(5‐pyridinyl)‐1,3 benzoic acid) for trace detection of PGA was designed and synthesized by a solvothermal method.Zn‐PBAcould detect the level of PGA in normal human physiological urine environment (pH range from 5.5 to 7.5) and has the characteristics of high selectivity and sensitivity, rapid response (<210 s), low limit of detection (LOD = 1.96 × 10−6 M), and so forth. The irreversible sensing of PGA proves that PGA caused the structural collapse ofZn‐PBA. This paper provides a specific sensor for detecting trace PGA level for evaluating the EB/S content intake by the human body.