A brazing sheet for flux-free brazing, comprising: a core material; a brazing material disposed on at least one surface of the core material; and a thin skin material disposed on the brazing material, wherein: the core material is made of an aluminum alloy having a higher melting point than that of the brazing material, wherein the aluminium alloy is a 3000 series alloy or 6000 series alloy of the JIS alloy classification; the brazing material is made of an Al-Si-Mg based alloy containing 5 to 13 mass% of Si, 0.2 to 1.5 mass% of Mg, 0.001 to 0.1 mass% of Ti, 0.0001 to 0.02 mass% of B and up to 0.6 mass% of Fe as an unavoidable impurity, and optionally 0.01 to 0.5 mass% of Bi, 0.1 to 5 mass% of Zn, 0.01 to 0.1 mass% of In, 0.01 to 0.1 mass% of Sn and 0.05 to 0.5 mass% of Cu; and the brazing material has a thickness of 25 to 250 μm; the thin skin material is made of an aluminum alloy being a pure Al based alloy or an Al-Mn based alloy, having a higher melting initiation temperature than that of the brazing material and having Mg controlled to less than 0.05 mass%, and has a thickness of 5 to 30 μm; the thin skin material and the brazing material are joined with clad rolling; and a content of oxides of aluminum and magnesium present at an interface between the brazing material and the thin skin material is 0.1 ppm or less in weight ratio with respect to the entire clad material. a core material; a brazing material disposed on at least one surface of the core material; and a thin skin material disposed on the brazing material, wherein: the core material is made of an aluminum alloy having a higher melting point than that of the brazing material, wherein the aluminium alloy is a 3000 series alloy or 6000 series alloy of the JIS alloy classification; the brazing material is made of an Al-Si-Mg based alloy containing 5 to 13 mass% of Si, 0.2 to 1.5 mass% of Mg, 0.001 to 0.1 mass% of Ti, 0.0001 to 0.02 mass% of B and up to 0.6 mass% of Fe as an unavoidable impurity, and optionally 0.01 to 0.5 mass% of Bi, 0.1 to 5 mass% of Zn, 0.01 to 0.1 mass% of In, 0.01 to 0.1 mass% of Sn and 0.05 to 0.5 mass% of Cu; and the brazing material has a thickness of 25 to 250 μm; the thin skin material is made of an aluminum alloy being a pure Al based alloy or an Al-Mn based alloy, having a higher melting initiation temperature than that of the brazing material and having Mg controlled to less than 0.05 mass%, and has a thickness of 5 to 30 μm; the thin skin material and the brazing material are joined with clad rolling; and a content of oxides of aluminum and magnesium present at an interface between the brazing material and the thin skin material is 0.1 ppm or less in weight ratio with respect to the entire clad material. the core material is made of an aluminum alloy having a higher melting point than that of the brazing material, wherein the aluminium alloy is a 3000 series alloy or 6000 series alloy of the JIS alloy classification; the brazing material is made of an Al-Si-Mg based alloy containing 5 to 13 mass% of Si, 0.2 to 1.5 mass% of Mg, 0.001 to 0.1 mass% of Ti, 0.0001 to 0.02 mass% of B and up to 0.6 mass% of Fe as an unavoidable impurity, and optionally 0.01 to 0.5 mass% of Bi, 0.1 to 5 mass% of Zn, 0.01 to 0.1 mass% of In, 0.01 to 0.1 mass% of Sn and 0.05 to 0.5 mass% of Cu; and the brazing material has a thickness of 25 to 250 μm; the thin skin material is made of an aluminum alloy being a pure Al based alloy or an Al-Mn based alloy, having a higher melting initiation temperature than that of the brazing material and having Mg controlled to less than 0.05 mass%, and has a thickness of 5 to 30 μm; the thin skin material and the brazing material are joined with clad rolling; and a content of oxides of aluminum and magnesium present at an interface between the brazing material and the thin skin material is 0.1 ppm or less in weight ratio with respect to the entire clad material.