Provided are an electric connector combination and a connecting element thereof. The connecting element comprises a base part, a first connecting part, a second connecting part and an elastic buckling arm. The base part has an upper surface and a lower surface which are opposite to each other. The first connecting part comprises two first protruding ribs which protrude upwardly at intervals from the upper surface of the base part, and two first clamping grooves which are respectively arranged on two opposite inner sides of the two first protruding ribs and respectively extend in the front-rear direction. The second connecting part comprises four vertical extension walls extending downwardly at intervals from the lower surface of the base part, and four first clamping flanges respectively extending horizontally from the four vertical extension walls. The elastic buckling arm extends from one end of the base part, and is provided with a first positioning part arranged on the upper surface and a second positioning part arranged on the lower surface. The connecting element enables two cable connector assemblies to be combined together and then to be fixed on an application apparatus, and is convenient to install.