The constitution and characteristic of immateriality capital in the knowledge-type enterprises were introduced out that patents were the core of such kind of enterprises.The methods for patents to promote the enterprise were represented from strategic attack, strategic defense and positioning. Due to the high uncertainty of patents, the enterprise value would be underestimated when DCF method was used in patentevaluation. Regarding the patent as the products' call option , and inputing five variables affecting the real option price to the balck-sholes pricing model, the real option value of the enterprise patent could be drawn accordingly.