Petrography is a geological study on several aspects which are formation of rock, composition of the rock, systemic classification on that rock as well as it relations with geological process. Generally, macroscopic term is used to explain hand specimen while microscopic term is used to explain thin section specimen. This research was conducted to determine mineralogy of rock using thin section through microscope petrography. Study area of this research is located at north side of Kelantan states involving 25 km2 areas of Ulu Sokor under Tanah Merah district bounded by latitude between 05° 37'30" N until 05° 40' 00" N and longitude between 101° 57'30" E until 102° 00'30" E. In the research areas, there are several different rock sedimentary rock lithologies that exist which are sandstone interbedded with mudstone also interbedded sandstone and siltstone which belong to Sokor Formation or also known as Telong Formation and lastly a metamorphic rock of schist part of Taku schist formation. Using petrography analysis, sandstone of the study area is identified as feldspathic litharenite sandstone based on the mineral abundance of 43.40% quartz, 31.60% rock fragment and 25.00% feldspar. Metamoprhic rock of schist is named after it mineral abundance which is quartz-mica schist.