Nowadays, the automotive industry is growing so then the company's competition is increasing. These requires of companies are to reduce the level of efficiency process and effectiveness process. Which has become a common problem is there have processes that do not provide added value (non value added), especially in the unpacking part process. PT XXX is an automotive manufacturing company specialized in assembly and distribution. All components of the car variant are stored in the factory warehouse before being produced. One of them is the STP (small trim part) component, which is the small car component. The purpose of this research is to provide a proposed improvement so that the STP unpacking process can be run effectively and the facility layout can be more efficient. The approach taken in this research is lean manufacturing using Value Stream Mapping (VAM) and Process Activity Mapping (PAM) tools. Then it will be simulated by ProModel software. Activities that occur in the warehouse and become research samples are Unpacking activities. This Unpacking activity consists of: (1) The preparation process for laying the box, (2) The unpacking process is the removal of components from the box, (3) The process of calculating the component quantity manually, (4) The process of scanning data (barcode scanning), (5) The process of inserting components into the blue box rack according to the location of the part number. Based on the results of observation, interviews, and identification using the PAM tool, with the seven waste type approach proposed by Dr. Shiego Singo, 2003, found some waste or non-value added (NVA) and necessary non value added (NNVA) activities in the unpacking process and the unpacking area layout becomes unsystematic. In the processes above, there are many activities that are neccesary non value added activities (NNVA), namely the operator's activity to prepare material lists, placing a large box that will be unpacked to the floor randomly, taking the empty boxes for store components that are not included in the material list, activities operators take unpacking equipment, open plastic components to check the quantity of components, look for plastic components that match the location of the blue box, and re-insert the small box into the large box. After doing the identification, Value Stream Mapping (VSM) is made to do easier improvements than before. The improvement given is to hold supermarket rack in the unpacking area of STP, with this improvement some of the main activities of the unpacking process can be reduced, namely to (1) unpacking process namely the removal of components from the box, (2) inserting components into supermarket rack according to location, (3 ) data entry process (barcode scanning). To be a comparison with the initial system so that the improvements can work in accordance with the reality in the field, the simulation of the model is using by ProModel application. The results of this study are expected to minimize the processing timing and to modification of STP unpacking area layout with the best improvement of the alternatives given during system simulation.