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The BL Lacertae OJ 287 is a supermassive black holes binary (SMBHB) systemwith complex physics of its irregular flares. During 2016 October -- 2017 Aprilperiod, a surprising outburst in the X-ray, UV and optical bands was detected,while no variability was seen in the $\gamma$-ray light curve. During theoutburst, the X-ray light curves were dominated by the soft X-rays, whose peakin the luminosity was $\sim$ $10^{46}\text{erg}~\text{s}^{-1}$ -- more than 10times higher than the mean level before the outburst -- and a"softer-when-brighter" phenomenon was exhibited. These above phenomena havebeen reported by some previous works. The hardness ratio showed negligibleevolution with flare time and soft X-ray luminosity. Critically, the luminosityof the soft X-rays decayed following a power law of $t^{-5/3}$ which occurs inmost tidal disruption events (TDEs), and similar trend can be seen in UV andoptical bands during the soft X-ray declining period. Helium and oxygen narrowemission lines are strengthened prominently in the optical spectra ofpostoutburst epochs, that could be attributed to the surrounding gas appeareddue to TDE. We discuss three possible origins of the event, including the jet'sprecession, the aftereffect of the black hole-disk impaction and the TDE. Ourresults show that the TDE is the more likely scenario to explain the outburst.

A possible tidal disruption event candidate in the black hole binary system of OJ 287