A vapor chamber device and a manufacturing method are disclosed. The vapor chamber has a housing and multiple independent chambers. The housing includes two shells opposite to each other. The independent chambers are formed between the two shells. Each independent chamber contains a working fluid and has at least one diversion bump and a capillary structure. The diversion bump is formed on an inner surface of the second shell, and the capillary structure is mounted on the diversion bump. When the vapor chamber device is vertically mounted to a heat source, the independent chambers at an upper portion of the vapor chamber device still contain the working fluid. The working fluid in the independent chambers may not all flow to a bottom of the vapor chamber device. Therefore, a contact area between the working fluid and the heat source is increased and heat dissipation efficiency is improved.