Anti-tumor necrosis factor alpha (anti-TNFα) agents are second-line treatment modalities for patients with ankylosing spondilitis after non-steroidal anti-inflammatory drugs, and are commonly used for different inflammatory rheumatic diseases. Development of malignancy is still one of the most feared side effects, with controversial results. In this paper, we present an ankylosing spondylitis patient with concomittant early stage chronic lymphocytic leukemia (CLL) who is currently under treatment with infliximab without progression for the past 5 years.