The embedded Java processor can directly run byte-code, greatly enhance the running speed and reduce the demand for resources. However, simple garbage collectors and pure generational collectors usually require relative large resources and introduce relative long pause time of all the program threads, which are not particularly suitable for the embedded java processor. This paper gives the analysis and research of the objects allocation feature and the age distribution characteristic in embedded Java processor environment, and proposes an improved generational garbage collector IGCEJ which is suitable for the embedded Java processor, with higher collection efficiency and lower system resources occupancy. In young generation, we adopt a kind of un-stop-the-world strategy, and objects allocation and promotion perform concurrently. As to the mature space, we apply lazy buddy system scheme integrated with mark-sweep algorithm in the garbage collection.