Selenium is an essential micronutrient that is beneficial to human health. Selenium-containing drugs have been developed as antioxidants, anti-inflammatory, and anticancer agents. However, the synthesis of selenium-containing chalcones has not been fully explored. Therefore, we report the synthesis of novel selenophene-based chalcone analogs and reveal their biological activities as anticancer agents. Among the seven synthesized molecules, compounds 6, 8, and 10 exhibited anticancer activity with IC50 values of 19.98 ± 3.38, 38.23 ± 3.30, and 46.95 ± 5.68 μM, respectively, against human colorectal adenocarcinoma (HT-29) cells. Clonogenic assays and Western blot analysis tests further confirmed that compound 6 effectively induced apoptosis in HT-29 cells through mitochondrial- and caspase-3-dependent pathways.