The flavonoids (POFs) from the leaves of Platycladus orientalis (L.) Franco were purified using six different macroporous adsorption resins including polar resins NKA-9 and ADS-F8, semi-polar resins ADS-17 and AB-8, and non-polar resins D101 and ADS-5. Among semi-polar resins, AB-8 demonstrated the best adsorption and desorption capacities with an adsorption ratio of 86% and a desorption ratio of 52%. According to the Simultaneous Thermogravimetry-Differential Scanning Calorimetry (STA/TG-DSC) analysis, POFs showed three thermally decomposed temperatures (347.6 °C, 437.5 °C and 494.8 °C). The main flavonoids in POFs were identified as esculin, amentoflavone, glabridin, and afromosin. Meanwhile, POFs in the dosage range of 25 to 400 μg mL-1 showed a significant anti-inflammatory effect on lipopolysaccharide (LPS)-induced RAW 264.7 mouse macrophage cells, which could inhibit the secretion of NO, IL-6, and TNF-α through the inhibition of inflammatory-related gene expressions.