Warehouse management system is an important part of supply chain lines in a company. The assist of barcode scanners has eased the workers in their process of receiving, storing, and issuing materials as they do not need to do paper works anymore. However, the usage of barcode scanners is limited due to the mobility. Hence a mobile warehouse management system is developed to use android scanner to replace the traditional barcode scanner. Different from barcode scanner, android scanner has embedded operating system allowing workers to use the system when they are scanning or away from computers and laptops. There are two main modules in this system which are inventory management subsystem, and warehouse mapping subsystem. Inventory management subsystem contains the basic warehouse management that allow users to scan barcode and generate reports for users to read. Whereas warehouse mapping subsystem provides display of map on screen for users to know the location of each rack and optimizes the route to the rack. The system is developed in Xamarin platform where the native library and .NET library can be used. The result of this system will be an android application that is installed on an android scanner, which its model is MC3300x Mobile Computer.