The assessment of penile cancer on the basis of clinical findings alone can often result in inaccurate staging and suboptimal treatment. Imaging of primary penile cancer and metastatic lymphadenopathy can help optimize planning of both primary tumor resection and treatment for lymph node metastases. Magnetic resonance (MR) imaging is the most accurate imaging modality in the assessment of primary penile cancers, which usually manifest as solitary, ill-defined infiltrating tumors that are hypointense on both T1- and T2-weighted MR images. T2-weighted MR imaging allows delineation of the tumor margin and of any extension into the penile shaft. On gadolinium-enhanced T1-weighted images, the tumors enhance to a greater extent than do the corpora cavernosa. In addition, the recently introduced technique known as lymphotrophic nanoparticle-enhanced MR imaging can help identify metastatic lymph node disease. However, further studies will be needed to determine the role of this imaging technique in clinical practice. Computed tomography does not clearly depict the local extension of primary penile cancer; however, it is useful in assessing metastases and postoperative complications.