An electrical connector assembly and a connecting member thereof, the connecting member comprises: a base portion having an upper surface and a lower surface which are opposite. A first connecting portion comprising two first protruding ribs spaced apart from each other and protruding upwardly from the upper surface of the base portion and two first latching grooves respectively provided at opposite inner sides of the two first protruding ribs, and the two first latching grooves extends along a front-rear direction. A second connecting portion comprising four upright extending walls spaced apart from each other and extending downwardly out from the lower surface of the base portion and four first latching flanges respectively extending horizontally out from the four upright extending walls. A resilient latching arm extending out from one end of the base portion, having a first positioning portion provided to an upper surface thereof and a second positioning portion provided to a lower surface thereof. The connecting member can assemble two cable connector assemblies together and then fix them to an application device, which is convenient during assembling.