Abstract Synthetic medicinal products are expensive and may have serious side effects. In addition, other antimicrobial agents have become increasingly required due to antibiotic resistance. To overcome these problems, people have used medicinal plants for years as a source of medication. Milk thistle ( Silybum marianum L.) has been used for decades to treat various chronic illnesses. This study aimed to verify the chemical profile of S. marianum using gas chromatography/mass spectrometry (GC/MS) and evaluate the plant extracts’ anti-inflammatory, anticoagulant, and antioxidant activities. Results revealed that extracts from the plant contain significant amounts of triterpenes, tetraterpenes, oxygenated hydrocarbons, and small amounts of hydrocarbons. Results also showed that at a dose of 0.5 mg/ear, the seed extract significantly reduced xylene-induced edema in mice; however, the water extracts reduced croton oil-induced edema with a percent inhibition of 84.61 ± 4.61 % at the same dose. Moreover, the results showed that the methanolic seed extract was the most potent in anticoagulant activity. In contrast, the n -butanol extract showed the highest DPPH free radical scavenging activity (IC 50 = 0.021 ± 0.006 mg/mL). This study highlighted the anti-inflammatory, anticoagulant, and antioxidant potential of S. marianum L. and the medicinal importance of natural phytochemicals isolated from this medicinal plant.