Petrochemical characteristics of Permo-Triassic granitoids from five regions (i) Mung Loei, (ii) Phu Thap Fah -Phu Thep, (iii) Phetchabun, (iv) Nakon Sawan -Lobburi, and (v) Rayong -Chantaburi along the Loei Fold Belt (LFB), northeastern Thailand were studied. The LFB is a north-south trending 800 km fold belt that hosts several gold and base-metal deposits. The granitoids consist of monzogranite, granodiorite, monzodiorite, tonalite, quartz-syenite, and quartz-rich granitoids. These are composed of quartz, plagioclase, and K-feldspar with mafic minerals such as hornblende and biotite. Accessory minerals, such as titanite, zircon, magnetite, ilmenite, apatite, garnet, rutile, and allanite are also present. Magnetic susceptibilities in the SI unit of granitoids vary from 6.5 × 10 −3 to 15.2 × 10 −3 in Muang Loei, from 0.