Marine clay is a soft soil and can be found in areas with extensive coastlines and river networks. Engineering problems can arise from this type of soil. Its high plasticity and low permeability can cause settlement and instability. Thus, an adequate site investigation and geotechnical studies are crucial and should be emphasized for projects in areas with marine clay deposits. This paper aims to determine the characterizations of marine clay samples collected from Batu Kawan, Penang, which is part of the Northern West Coast of Malaysia, by laboratory tests. The characterization study consists of geotechnical, chemical, and mineralogical properties. Based on unified soisl classification system and the plasticity chart, the soil was classified as silt with high plasticity. The other geotechnical properties show results of 91.7%, 59%, 48%, 11%, 2.6, 19.2%, and 1562 kg/m3 of moisture content, liquid limit, plastic limit, plasticity index, specific gravity optimum moisture content, and maximum dry density, respectively. The soil also had a low shear strength of 78 kN/m2. Meanwhile, the chemical properties revealed that the soil contained 8.2% organic matter, and X-ray fluorescence (XRF) analysis indicated the most dominant chemical compounds were found to be Silica, SiO2, and Aluminum, Al2O3, where the values were 58.2% and 14.4%, respectively. X-ray diffraction (XRD) was conducted to observe the mineralogy present in the soil and indicate the presence of Quartz and Kaolinite, mainly. The characterizations of Batu Kawan marine clay were compared with other studies on marine clay from west coast of Malaysia and found good agreement.