The invention discloses a double-sounder system suitable for marine geological survey. The double-sounder system comprises a clamp base device, an energy transducer and a depth instrument. The depth instrument comprises a conversion switch, a junction box and the energy transducer. The conversion switch is electrically connected with one end of the junction box, and the other end of the junction box is electrically connected with the energy transducer. The distributed arrangement is adopted so that the problem of the background technology can be greatly solved. Two sounders are arranged at different positions of the ship so that the influence of the stream diversion cover and the scientific sounder thereof on the sounders can be reduced, the sonar signals of different positions are read under different conditions and the thus the accurate water depth data can be acquired.