In this book the existence and uniqueness of fuzzy linear integro-differential equations of Volterra type is proved, also the analytic, approximated, and numerical solutions of these type of equations are discussed. Also the concept of fuzzy reduction formula to reduce fuzzy linear differential equations, fuzzy linear Volterra integral equations, and high order fuzzy linear integro-differential equations of Volterra type to first order fuzzy linear integro-differential equations of Volterra type are introduced. Tow type of fuzzy functions are used to define functions in each equation, fuzzy valued functions and fuzzy bunch function.