In ultra-short and ultra-intense laser facilities based on Optical Parametric Chirped Pulse Amplification (OPCPA) technologies, optical parametric fluorescence delivered by amplification process is one of the main factors degrading the temporal signal-to-noise ratio at the final focal end. Currently, there is not any effective control method for optical parametric fluorescence in multi-stage amplifiers, and it is a critical issue that urgently requires resolution. This paper proposes a technical scheme for improving signal-to-noise ratio based on wavefront-controlled OPCPA. A large phase difference is introduced between the optical parametric fluorescence and signal pulse, to make the parametric fluorescence to obtain a lager defocused amount compared with the signal pulse. After that, the active control of optical parametric fluorescence at the final focal end could be realized, and the temporal contrast of the focused laser pulse would be improved. Experimental investigations were conducted in OPCPA amplifier of Shenguang-II 5 Petawatt (SG-II 5PW) ultra-short and ultra-intense laser facility, from which 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 of 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 observed notable changes in the focal spot size of the signal, and could achieve a 2.8-fold difference in the focal spot sizes between the parametric fluorescence and signal. Finally, utilizing wavefront control technology, combined with a spatial filter featuring a 75µm aperture, we reduced the incoherent noise front pedestal of the amplified signal pulse, achieving a two-order-of-magnitude improvement in signal-to-noise ratio. This technology could 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.