The current embedded devices are growing rapidly in the multi-core, and these demand fast boot time. But method of previous boot uses core only one. The method includes parallel techniques and modification of CPU Frequency policy. Parallel methods, after analyzing the Android boot process with analysis tool, applied to location where a lot of CPU operation. CPU Frequency policy is modified for high performance of core. The proposed method was applied to S5PV310 dual core and Exynos4412 quad core embedded system. As a result of the experiment, we found that the proposed method makes boot time fast about 20.71% and 31.34% in dual core and quad core environment as compared with the previous method.