Unstable angina (UA) is a coronary disease with a high mortality and morbidity worldwide. The present study aimed to use non‑invasive techniques to identify urine biomarkers in patients with UA, so as to provide more information for the early diagnosis and treatment of the disease. Based on metabolomics, urine samples from 28 patients with UA and 28 healthy controls (HCs) were analyzed using ultra‑high‑performance liquid chromatography‑quadrupole time‑of‑flight mass spectrometry (UPLC‑Q‑TOF/MS). A total of 16 significant biomarkers that could distinguish between patients with UA and HCs, including D‑glucuronic acid, creatinine, succinic acid and N‑acetylneuraminic acid, were identified. The major metabolic pathways associated with UA were subsequently analyzed by non‑targeted metabolomics. The results demonstrated that amino acid and energy metabolism, fatty acid metabolism, purine metabolism and steroid hormone biosynthetic metabolism may serve important roles in UA. The results of the current study may provide a theoretical basis for the early diagnosis of UA and novel treatment strategies for clinicians. The trial was registered with the Chinese Clinical Trial Registration Center (registration no. ChiCTR‑ROC‑17013957) at Tianjin University of Traditional Chinese Medicine.