This disclosure relates to an electrical connector module and an electronic device including the same. The electrical connector module includes: a circuit board formed with two lateral notches and a main notch interposed therebetween; an electrical connector mounted on the circuit board and including an insulating housing; and a retaining element including: two support arms respectively formed on the circuit board relative to the lateral notches; two flexible connecting arms respectively extending from the support arms through the lateral notches; and an engaging seat connected between the flexible connecting arms and suspended under the main notch so as to cooperate with the insulating housing to define a plugging space.