As the title of the book suggests, the topics of this book are organized into two parts. The first part points out the fuzzy differential equations and the second one is related to the fuzzy integral equations. The book contains nine chapters that six chapters are about fuzzy differential equations and three of them are about fuzzy integral equations. In each part, the chapters’ authors are going to discuss the topics theoretically and numerically.All researchers and students in the field of mathematical, computer, and also engineering sciences can benefit from the subjects of the book.