The present invention relates to thermally stable oral rotavirus vaccine formulations comprising one or more rotavirus reassortant or attenuated rotavirus strains, a pharmaceutically acceptable calcium salt, adipic acid, sucrose, and sodium phosphate, wherein each of the one or more rotavirus reassortant or attenuated rotavirus strain is stable for 7 days at 37?C., for 45 days at 25?C. and for 2 years or more at 2-8?C. The calcium containing formulations of the invention may further comprise one or more excipients which are present in an amount that is effective to optimize the calcium ions free in solution to stabilize the rotavirus particles. In embodiments of the invention, the formulation comprises a surfactant, such as polysorbate 80. The invention also relates to methods of using the rotavirus vaccine compositions of the invention to prevent rotavirus infection, or to reduce the likelihood of infection or to prevent, ameliorate, or delay the onset or progression of the clinical manifestations thereof.