We report the detection of a probable $gamma$-ray quasi-periodic oscillation (QPO) of around 314 days in the monthly binned 0.1 -- 300 GeV $gamma$-ray {it Fermi}-LAT light curve of the well known BL Lac blazar OJ 287. To identify and quantify the QPO nature of the $gamma$-ray light curve of OJ 287, we used the Lomb-Scargle periodogram (LSP), REDFIT, and weighted wavelet z-transform (WWZ) analyses. We briefly discuss possible emission models for radio-loud active galactic nuclei (AGN) that can explain a $gamma$-ray QPO of such a period in a blazar. Reports of changes in the position of quasi-stationary radio knots over a yearly timescale as well as a strong correlation between gamma-ray and mm-radio emission in previous studies indicate that the signal is probably associated with these knots.
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