The focusing properties of a red far detuning high power standing wave for a thermal atomic beam are studied through numerical simulation. The result shows that this type of standing wave is possible to be used for atom lithography. The FWHM of the line width deposited on the substrate at the focal plane of the thermal atomic beam is about 20 nm, the contrast is 4～5, with beam waist w 0=0.1 mm, power P=7 W respectively. A proposal of using enhanced cavity to increase the line contrast to 7 and decrease the FWHM of the line width to 5 nm～10 nm is put forward.