The invention discloses a flame retardant yarn, a fabric and clothing capable of preventing the splashing of molten metal. The range of wool mass contained in the flame retardant yarn as a percentageof flame retardant viscose mass of silicone nitrogen series is 30.769%-157.895%. The flame retardant yarn, the fabric and the clothing contain the three kinds of fiber of wool, silicon nitrogen flameretardant viscose and nylon; nylon is a non-flame retardant fiber; the mass ratio of the three kinds of fiber is as follows: 20-60% of wool, 38-65% of flame retardant viscose of the silica nitrogen series, and 2-15% of nylon. The flame retardant fabric and clothing conform to the aluminum water splash test of EN ISO 9185-2008, the mass of the protective splash aluminum water is larger than or equal to 100 g, larger than or equal to 200 g or larger than or equal to 350 g, and accords with the molten iron splash test of EN ISO9185-2008, the mass of the protective splash molten iron is larger than or equal to 60 g, larger than or equal to 120 g or larger than or equal to 200 g; meanwhile the flame retardant test of EN ISO 15025-2003A1 is satisfied, the afterflame is less than or equal to 2 seconds, smoldering is less than or equal to 2 seconds, no melting and dripping phenomenon appears, and no burning holes appear; the flame retardant yarn meets the test of EN ISO 5077-2008, the washingshrinkage rate is larger than or equal to -10% and less than or equal to 10%.