Stimulated Raman scattering (SRS) technology is a powerful method to obtain coherent radiation and explore molecular structure. SRS of O-H stretcing vibration in water molecules is studied, and it is found that SRS of water molecules excited by 532 nm laser is greatly enhanced by the application of CW (continuous-wave) seeding laser with 650 nm. When 1 mW CW laser power is introduced, the normalized SRS intensity of O-H stretching vibration at 3392 cm-1 is increased by an order of magnitude, and at the same time, two new lower frequency shoulder peaks (3356 cm-1 and 3288 cm-1) are also observed. The introduction of CW seeding laser not only lowers the threshold of SRS, but also increases the intensity of SRS. The mechanism of the enhancement of SRS intensity is attributed to that the frequency difference between pump laser (532 nm) and CW seeding laser (650 nm) matches the O-H stretching vibrational frequency of water molecule, resulting in the resonance between molecular vibration frequency and the difference frequency of the two lasers. This work shows the possibility of using resonance methods to enhance weak Raman vibration modes.