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In this manuscript, a 6.4yr optical quasi-periodic oscillations (QPOs) isdetected in the quasar SDSS J075217.84+193542.2 (=\obj) at a redshift 0.117, ofwhich 13.6yr-long light curve from CSS and ASAS-SN directly described by asinusoidal function with a periodicity 6.4yr. The 6.4yr QPOs can be furtherconfirmed through the Generalized Lomb-Scargle periodogram with confidencelevel higher than 99.99\%, and through the auto-correlation analysis results,and through the WWZ technique. The optical QPOs strongly indicate a centralbinary black hole (BBH) system in \obj. The determined two broad Gaussiancomponents in the broad H$\alpha$ can lead to the BBH system with expectedspace separation about 0.02pc between the expected two central BHs withdetermined virial BH masses about $8.8\times10^7{\rm M_\odot}$ and$1.04\times10^9{\rm M_\odot}$. Meanwhile, we check the disk precessions appliedto explain the optical QPOs. However, under the disk precession assumption, thedetermined optical emission regions from central BH have sizes about $40{\rmR_G}$ two times smaller than sizes of the expected NUV emission regions throughthe correlation between disk size and BH mass, indicating the disk precessionsare not preferred. And due to the lower radio loudness around 0.28, jetprecessions can be also totally ruled out. Furthermore, only 0.08\% probabilitycan determined as the QPOs mis-detected through light curves randomly createdby the CAR process, re-confirming the reported optical QPOs.

A 6.4yr optical quasi-periodic oscillations in SDSS J075217.84+193542.2: a new candidate for central binary black hole system