A medical kit includes a liquid storage container in which a liquid is preliminarily stored, syringes, a first connector for connecting the liquid storage container and the syringes, and a regulating mechanism for collectively regulating limits of movement of gaskets of the syringes and. The syringes are collectively filled with the liquid by conducting an operation to feed out the liquid in the liquid storage container in a condition in which the liquid storage container and the syringes and in an empty state are connected through the syringes, until the limits of movement are regulated.