Abstract: The micro-ecological feed additives had advantages that they were safe,effective,no pollution,no drug resistance and no residue,they met the demand for developing ecological breeding and green food and they were a focus in developing and researching feed additives. So,they had broad development prospect in the application of feed additives. In recent years,the positive results were achieved in researching and developing micro-ecological feed additives. The aspects such as kinds,characters,action mechanism and application in livestock and poultry production of micro-ecological feed additives were reviewed by the writer.