Primary ovarian lymphomas constitute 0.5% of all ovarian malignancies. We report one such case in a middle-aged woman who presented with a bilateral ovarian tumor. Bilateral oophorectomy with salpingectomy was sent for frozen section analysis that revealed a round cell tumor. Final histopathology showed a mitotically active small round blue cell tumor arranged in diffuse sheets and chords with an evident starry-sky pattern. Extensive immunohistochemistry (IHC) panel was performed. Histopathology along with IHC did not classify the tumor into diffuse-large-B cell-lymphoma or Burkitt lymphoma and a final diagnosis of high-grade B cell lymphoma (HGBL) was made. This case is presented for its rarity and to discuss the challenges on IHC to subclassify a lymphoma as HGBL. Although rare, the possibility of primary ovarian non-Hodgkin lymphoma should be kept in mind when dealing with bilateral ovarian tumors as a timely and accurate diagnosis can save unnecessary surgeries and improve outcome.