An organic light emitting diode (OLED) display device and method of fabrication that includes a substrate having a device region, an outer dam region and an encapsulation region. The encapsulation region includes an inner dam region, an outer dam region and an encapsulation region that correspond to the device region. An encapsulation agent is formed in the encapsulation region of the encapsulation substrate, and filling dams are formed of the same material in the outer dam region and the inner dam region of the encapsulation substrate.