The invention relates to an automatic trace sample feeding device of an electrophoresis detector and a manufacturing method and control method of the automatic trace sample feeding device. The automatic trace sample feeding device comprises a microfluid sample feeding module, a microfluid sample discharging module, a first micro electromagnetic driving pump, a second micro electromagnetic driving pump, a first micro partitioning valve, a second micro partitioning valve, a high-voltage power supply, a sample bottle, a buffer liquid bottle, a sample waste liquid bottle, a waste buffer liquid bottle, a control circuit board, a control system, a storage battery and a double-layer bracket. The automatic trace sample feeding device is applicable to automatic trace sample feeding of a portable capillary electrophoresis detector and a microfluid electrophoresis chip, precise, automatic and repeated sample injection is achieved, operation errors are reduced, the operation efficiency is improved, artificial interference is avoided, a uniform sample feeding amount of each time is ensured, meanwhile a rapid capillary tube replacing interface is available, and sample pollution caused by the situation that a capillary tube is not easily cleaned on site is avoided.