Abstract: In this paper, a new type of riser for twin holes in monobores is proposed to solve the problems which come up along with the common monobore twin-well techniques, such as general collision in the trip-in of casing string and the simultaneous injection of a large amount of cement slurry during cementing operation. This riser eases the directional angle build-up, improves the cementing quality, and simplifies the operation by presetting specialized baffle to break up the space to make up two independent pipe strings. Using finite element analysis software, the stress, bending moment and structural stability calculation of Q345B monobore twin-well risers with dimensions of Ø914.4 mm×22.225 mm are conducted in Chengbei oilfield in Bohai Sea waters, based on the summer and winter oceanic environment conditions every once 50 years in Bohai Sea.The results show that the safety factors of stress, bending resistance, and column structure displacement all meet the standard requirements, presenting sound safety and reliability of this new risers. This research provides a new idea for the development of Chengbei oilfield in Bohai Sea, however, further research is needful for deep-sea oil fields development.