Friction plug welding (FPW) of 2014 Al alloy in 4mm thickness is carried out and the microstructures, mechanical properties and fracture mode of the joint are analyzed. The result shows that the FPW joint microstructures could be divided into three different regions including welding seam zone, HAZ and base metal zone. The welding seam consists of refined and equiaxial recrstallized grains. Mechanical experiment shows that the technological parameters, such asfrictional pressure, friction time, tapered plug/tapered hole suited angles and welding speed can affect joint properties. The peak tensile strength of the FPW joint can reach 375 MPa as much as 79% of the base metal by selection of suitable welding parameters and joint structures. The analysis of the fracture surface morphology shows that it is ductile fracture.