In ultra-short and ultra-intense laser facilities based on optical parametric chirped pulse amplification (OPCPA) technologies, optical parametric fluorescence generated by the amplification process is one of the main factors degrading the temporal signal-to-noise ratio at the final focal end. Currently, there is no effective control method for optical parametric fluorescence in multi-stage amplifiers, representing a critical issue that urgently requires resolution. This paper proposes a technical scheme for improving the signal-to-noise ratio based on wavefront-controlled OPCPA. A large phase difference is introduced between the optical parametric fluorescence and the signal pulse, causing the parametric fluorescence to obtain a larger defocus compared with the signal pulse. Consequently, the active control of optical parametric fluorescence at the final focal end can be realized, and the temporal contrast of the focused laser pulse is improved. Experimental investigations are conducted in the OPCPA amplifier of the Shenguang-II 5 Petawatt (SG-II 5PW) ultra-short and ultra-intense laser facility. The experimental results indicate that in the OPCPA process, the wavefront of the pump light significantly affects the wavefront of the amplified signal. Furthermore, the higher the gain of the OPCPA amplifier, the stronger the impact on the wavefront phase of the signal. Simultaneously, by adjusting the wavefront of the input signal, we observe notable changes in the focal spot size of the signal and achieve a 2.8-fold difference in the focal spot sizes between the parametric fluorescence and the signal. Finally, utilizing wavefront control technology combined with a spatial filter featuring a 75 μm aperture, we reduce the incoherent noise front pedestal of the amplified signal pulse, achieving a two-order-of-magnitude improvement in the signal-to-noise ratio. This technology can be widely used in all OPCPA systems and possesses strong engineering applicability, with important implications for the performance advancement of global ultra-short and ultra-intense laser facilities.