Zearalenone (ZEA), which is one of the most prevalent wheat and corn seeds mycotoxins causes acute and chronic toxicities in ruminants, poultry, and aquatic animals. Among commercial toxin binders, only a few active charcoals have the significant ability to adsorb ZEA contamination; nevertheless, active charcoal is not considered a sound additive by the feed industry. This study aimed to screen and identify the ZEA-degradation compounds of the Zataria multiflora (Shirazi thyme) in the cattle rumen fluid. In this investigation, essential oil and different extracts (n-hexane, ethyl acetate, and methanol) of the aerial part of Shirazi thyme (at three concentrations of 0.5, 1, and 2 mg/ml) were screened to reduce ZEA contamination conditions (2 µg/ml) in rumen fluid. ZEA-content was analyzed by high-performance liquid chromatography (HPLC) with a fluorescence detector. In addition, Shirazi thyme phytochemical compounds responsible for eliminating ZEA were localized by HPLC-based activity profiling and then identified by mass spectrometry (LC-MS). Both n-hexane and methanol extracts of Z. multiflora, considerably remediated ZEA (63-78%) from rumen fluid. According to HPLC-based activity profiling of Z. multiflora extract and LC-MS analysis, two triterpene compounds, including ursolic and oleanolic acids were introduced as ZEA degradation agents. Z. multiflora could be recommended as a new botanical source, and ursolic and oleanolic acids could be introduced as new phytochemical compounds that degrade ZEA.