The invention discloses a scientific investigation drilling vessel comprising an engine room area, a mud area, a living area, a moon pool area and a releasing area of a Christmas tree and a blowout preventer. The engine room area is located on the stern and comprises three engine rooms which are arranged in a staggered manner and triangularly distributed. The mud area is arranged on the stern andcomprises a mud pump chamber, mud pool chambers and a mud mixing treatment chamber. The mud mixing treatment chamber is arranged on the different deck layers from the mud pump chamber and the mud poolchamber. The mud pool chambers are arranged around the mud pump chamber at intervals. The living area is arranged on the bow. Each cabin is composed of modular steel plates. The moon pool area is arranged in the middle of the vessel. The releasing area of the Christmas tree and the blowout preventer is arranged on the back of the moon pool area. The length of the vessel body is 150-180 m, the width of the vessel body is 28-33 m, and the height of the vessel body is 15-17 m. The scientific investigation drilling vessel is more compact in structure, the dimension of the vessel is greatly reduced, good economical efficiency and high efficiency are achieved, vessel functions can be effectively matched with economic expense, and good economic benefits are achieved.