Manufacturing of the EV will run alongside Mini’s production efforts in Oxford, where the EV will also be made.
Production at BMW's existing joint venture in China, BMW Brilliance Automotive (BBA), already caters for BMW demand in the domestic market.
BMW sold 560,000 cars in China last year, while 35,000 Minis found homes across the same timespan. BMW Germany built 1.15million cars in 2017.
So far, the plans for the new joint venture are only at the stage of a letter of intent, but BMW has alluded to more electric Mini models on the way, which would also be made by Great Wall.
The Mini Electric was demonstrated by a concept revealed last year, and first prototypes have since been spotted testing ahead of a 2019 launch. The production model will be toned down from the concept, with the highly stylised bodywork and yellow flashes on the exterior likely being diluted.
BMW already has three facilities in China under BBA - two production plants and a battery factory in Shenyang. Alongside the Mini EV production announcement, these are getting a boost in investment.
During the early stages of the Brexit process, BMW executives issued warnings about the future of Mini’s Oxford plant, which currently deals with demand for Minis in more than 110 markets.
A Mini spokesman told Autocar: "This announcement does not put into question Mini's commitment to our UK facilities, as demonstrated by our recent investment decisions, which include building the first electric Mini at Oxford."
The spokesman couldn't elaborate on the brand's plans following the first EV, however.