Diffuse large B-cell lymphoma (DLBCL), the most common type of non-Hodgkin lymphoma (NHL), is known to be associated with increased risk of second primary malignancies (SPM). The occurrence of more than one type of cancer in a single patient is considered a rare finding, either appearing at the same time (synchronous) or subsequently (metachronous). This study is to present this interesting case of a male patient diagnosed with DLBCL, basal cell carcinoma (BCC), and adenocarcinoma of colon metachronously. A case report from May 2012 to January 2022. Oncology Unit/Oncology Center Mansoura University, Egypt. A 43-year-old male patient, HCV positive, diagnosed from splenectomy with DLBCL, Stage IV. In 2012, the patient received 8 cycles of CHOP protocol and achieved complete remission. In 2016, he presented with a face ulcer, which was excised with adequate safety margins, and histopathological examination revealed BCC. In 2017, he presented with acute abdomen. Computed tomography (CT) showed a well-defined soft tissue mass at the distal part of the ascending colon and hepatic flexure with signs of intestinal obstruction. The patient underwent right hemicolectomy and double barrel ileotransverse colostomy, and the histopathological examination revealed grade II adenocarcinoma, Stage IIa. Then, he received 6 cycles of adjuvant de Gramont regimen. After that, CT and colonoscopy were free. In 2019, he presented with B symptoms and right axillary lymphadenopathy; biopsy revealed NHL of large-cell type in favor of high-grade follicular lymphoma. After receiving 4 cycles of DHAP protocol, PET/CT was negative. Yet, he refused autologous stem cell transplantation. In 2021, he presented with cervical lymphadenopathy and tumor lysis syndrome. Biopsy showed DLBCL. The patient is 43 years old, male, HCV positive, underwent splenectomy, was diagnosed with DLBCL, and received chemotherapy. All of these are considered risk factors for SPM. The patient received supportive treatment, and 3 sessions of hemodialysis were done. He has been lost to follow-up since January 16th, 2022. DLBCL increases the risk of SPM mostly due to immune dysfunction, immunosuppression, and the mutagenic effects of chemotherapy. Hence, regular screening of DLBCL patients and survivors is recommended.