East Java is an area with the potential to produce oil and gas. Oil and gas are hydrocarbon mix produced from the subsurface, sourced from matured organic materials, and migrated to be drilled to be produced into oil and gas. The methods to explore oil and gas are well logging and seismic methods. Combining both methods can obtain vertical and horizontal subsurface information. The study was performed by analyzing secondary data processing results of wells, seismic data, and ko chemistry data. Geochemical data were used to analyze source rock potentials in the study area. Source rock is rock containing organic materials to produce hydrocarbons. Therefore, this study aimed to determine source rock potentials. Using the three methods, it concludes that Field “X” as the study site in the northeast Java, can produce hydrocarbons on the northwest region of the study area because the source rock zone at Field “X” has a 3.87% TOC with type II kerogen. Although the source rock is immature, it can produce oil and gas.