This paper presents an experimental investigation of the welding of a glass-fiber-reinforced PP composite. The goals of this paper are to investigate the issues of local changes of the welding strength that depend on the heating time and the coupling agent (MAPP). Composite samples were prepared by using an extruding (for mixing) process and a hot-press method. The PP matrix was reinforced by unidirectional short glass fibers. The welding process for the specimens was carried out using a non-contact heated tool butt welding process. Tensile and fatigue tests were conducted to investigate the effects of the heating time parameter and the coupling agent. The highest weld strength dependent on the heating time was achieved with 94 % relative to the base strength of the material. The fatigue behavior of short-fiber-reinforced thermoplastic composites (polypropylene/20 % of volume fractions of E-glass fiber) is presented in terms of stress versus the number of cycles to failure. The specimens were fatigue tested at various percentages of their static tensile strengths at a load ratio R = 0.1 and frequency f = 5 Hz. An indefinite fatigue life was obtained at 35 % of the static damage initiation load for glass-fiber-reinforced specimens. Then, these specimen's maximum welding strengths and fatigue properties that were dependent on the heating time were compared.