Selenium is a semimetallic element lying in the group XVI of the periodic table with its chemical properties resembling sulfur. But owing to its relatively low electronegativity and large atomic radius comparing with sulfur, selenium also shows unique properties. This feature endows selenium-containing compounds with high reactivity and sensitivity. Although organic selenium chemistry has been developing very fast, the success introducing of selenium into polymer science is rather scarce. Fortunately, we have seen a drastic rising trend in the area of selenium-containing polymer for the past decade. Our research mainly focus on the preparation of selenium-containing polymers, their unique stimuli-responsive and dynamic properties, together with their diverse applications in the field of adaptive and biomedical materials.