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A novel flux-containing 4047 composite brazing filler metal was prepared by powder forging method. The microstructure and brazing performances of the self-made composite filler metal, commercial flux-cored and imported brazing filler metal were investigated comparatively. Experimental results showed that there are two endothermic peaks in the melting curve of the self-made composite filler metal, and the melting point of flux was relatively lower than that of the 4047 filler alloy. The spreading area of the self-made composite filler metal was 363 mm2, which was close to that of imported filler metal (353 mm2) and was significantly larger than that of flux-cored ones (311 mm2). Under the environmental conditions of 85% humidity and 35 ℃, the self-made and imported filler metals showed excellent moisture absorption resistance, while the flux-cored one showed a remarkable increase in mass due to moisture absorption of flux. The moisture absorption rates of the flux-cored ones placed in humid environment for 72 h, 144 h and 216 h were 3.88%, 4.02% and 4.27%, respectively. The results of microstructure analysis showed that the flux particles of the self-made composite filler metal were small in size and evenly distributed, which were firmly wrapped in the matrix of the 4047 filler alloy. The average fracture strength of the brazed AA6061/AA3003 dissimilar lap joints was 107.5 MPa, and the fracture position was located in heat-affected zone of the AA3003 side. The dense structure of the brazed seam showed that the self-made composite filler metal has good brazing performance and high brazed rate.