A pneumatic microvalve array was designed and fabricated using silicon/glass bulk micromachining and a new parylene bonding technique. The valve membrane is made of parylene, thus has very compact size (300 ?m x 300 ?m) and excellent chemical resistance. The operation of valves was characterized to reveal the effects of several parameters such as actuation and inlet pressure. The valve demonstrates a flow rate as high as 0.33ml/min in open state with 15.5psi inlet pressure, and very low leaking rate. With the proposed novel control logic, the microfabricated valve array device is expected to be very suitable for fluidic manipulation in integrated lab-on-a-chip systems in which aggressive chemicals are involved and high throughputs are required.