A boron-containing stainless steel having excellent hot workability and weldability and a good surface quality is proposed and is a boron-containing stainless steel comprising C: 0.001-0.15 mass %, Si: 0.1-2 mass %, Mn: 0.1-2 mass %, Ni: 5-25 mass %, Cr: 11-27 mass %, B: 0.05-2.5 mass %, Al: 0.005-0.2 mass %, O: 0.0001-0.01 mass %, N: 0.001-0.1 mass %, S: not more than 0.005 mass %, one or both of Mg: 0.0001-0.005 mass % and Ca: 0.0001-0.005 mass % and the remainder being Fe and inevitable impurities provided that a part of Si, Al, Mg, Ca and S is included as a non-metallic inclusion made of sulfide and/or oxysulfide.