Intravascular large B-cell lymphoma (ILBL) is a rare and difficult to diagnose subtype of large B-cell lymphoma. The most common locations of presentation are in the central nervous system and the skin, but there are reports of other organ involvement. Due to the indolence, nonspecific symptoms, and rarity of the disease, this form of lymphoma is most often diagnosed postmortem. In this article, we describe a case of ILBL that presented as a rapidly progressive acute axonal polyneuropathy. Acute axonal polyneuropathy is a common disease process with a wide differential diagnosis, but there is limited literature on its prevalence as the presenting symptom of ILBL. This patient was treated with R-EPOCH and intrathecal methotrexate with significant improvement in his polyneuropathy after 1 cycle, and complete remission after 6 cycles. Data on chemotherapy regimens and their success rates for this disease are lacking.