The aetiology of OAL is undefined, although much attention has been recently focused on determining whether OAL is caused by an autoimmune disorder, chronic antigenic stimulation or both. It is becoming evident that infectious agents underlying chronic eye infection, as Chlamydia, may play a role in ocular lymphomagenesis. The high prevalence of Chlamydophila psittaci in patients with OAL has suggested a potential oncogenic role for its tendency to cause chronic and persistent infections, although it has been documented an evident geographical variability and response to antibiotic treatment. For C. pneumoniae, the findings so far obtained are very limited not only for identification in OAL but also for the specific treatment with antibiotics. The recent molecular and cultural evidence of C. trachomatis in patients with OAL, seems to suggest that also this pathogen may contribute to pathogenesis of such lymphoma. The potential application of bacteria-eradicating therapy at local and systemic level may ultimately result in safer and more efficient therapeutic option for patients affected by these malignancies. Moreover, a close collaboration between experts in ophthalmology, infectious diseases and hematology will help, in the future, to effectively manage this disease. This review attempts to weigh the currently available evidence regarding the role that Chlamydia play in development of OAL and focuses on patients with OAL observed at our Institution.