Cosmic inflation is an Era of accelerated expansion in the very early universe. The idea of inflation was proposed to solve various cosmological problems faced by the hot big bang model. With the detection of cosmic microwave background radiation and its anisotropies, inflation has become an integral part of modern cosmology. One of the most important challenges now is to find a Standard Model of Inflationary Cosmology. I plan to discuss the realization of cosmic inflation in the framework of the supersymmetric grand unified model where a super-partner of right-handed neutrino plays the role of an inflaton. This provides an interesting trinification of inflationary cosmology, neutrino physics, and grand unified theories.