Abstract: A method, an apparatus and a system for automatically adjusting an opening degree of a fluid control valve, relating to the technical field of oil and gas exploration and development. The method includes: establishing a fluid control valve having an orifice structure in oil and gas production; using a numerical simulation method to obtain the influence law of minimum opening degree adjustment step on oil and gas production; obtaining relevant production test data of the oil and gas well, and calculating the total oil and gas production and the oil and gas production of each production layer based on the production test data of the oil and gas well; dividing the production layer segments into high, middle and low-production layers according to the production ratio of each production layer segment; respectively calculating the average productions of the high, middle and low-production layers.