Approximately, 15-20% of all cancers worldwide are caused by infectious agents. Understanding the role of infectious agents on cancer development might be useful for developing new approaches to its prevention. Mycoplasma genitalium is a clinically important sexually transmitted pathogen that has been associated with several human diseases. There have been a few studies suggestive of probable roles of Mycoplasma genitalium in cancer development, including prostate and ovarian cancers and lymphomas, but the role of this microorganism like other Mycoplasma species in neoplasia is still conjectural. Considering the prevalence of Mycoplasma genitalium infections and also the emergence of resistant strains, Mycoplasma genitalium needs more attention in the infectious agent cancer-causing research area.