A modular plug includes a main body and a fixing block. The main body includes an upper housing, a lower housing, and blades. The upper housing includes a first top surface defining slits for respectively retaining one contact and a first bottom surface defining a first cavity and indents extending from one sidewall of the first cavity. The first bottom surface includes wires being connected with one contact. The lower housing includes a second top surface, abutting against the first bottom surface of the upper housing, and a second bottom surface. The second top surface defines a second cavity and slots extending from one sidewall of the second cavity. The second bottom surface forms an elastic tab extending therefrom. The blades are respectively received in one indent. The fixing block is fitted in to the first cavity and the second cavity and includes fixing portions fixing cores of a cable.