The company has placed a firm order of eight ships, with options to build another four.
Deliveries are scheduled in 2022 and 2023.
Dalian-based StarOcean Marine mainly operates feeder container shipping services between China and Japan, and currently has a fleet of 13 boxships.
The company added a resale 1,800 teu boxship from Yangzijiang in December and named it A Fuji.
The order is the second major containership order Yangzijiang has received recently after Zhonggu Logistics ordered ten 4,600 teu ships at the yard.