In some foreign countries, it is more than 20 years since the study on technology for deepsea polymetallic nodule mining has been conducted, and many results have been achieved in this field. The authors assess briefly the results from the study of collection technology for the deepsea mining system in the world, and analyze the problems existing in the study of collection technology and the development of collector.Finally, the scheme for the development of modular self-propelled collector is proposed, in combination with China's situation.