The invention discloses an alloy wire for obtaining fine oxide in low alloy steel and a manufacturing method and application thereof, and belongs to the technical field of low alloy steel materials. Alloy powder coated by the alloy wire contains one or more of 10 to 50 mass percent of Ti powder, 5 to 25 mass percent of Mg powder, 5 to 25 mass percent of Zr powder, 2 to 10 mass percent of Al powder, and the balance of iron powder and unavoidable impurities; and the formulas that: Ti powder/Mg powder is more than or equal to 4, Ti powder/Zr powder is more than or equal to 2, and Ti/Al is more than or equal to 10 are met. The particle size of the alloy powder is 1 mu m to 1 mm, the thickness of a coated iron sheet is 0.2 to 1 mm, and the diameter of the alloy wire after drawing is 1 to 8 mm.The invention has the advantages that: when the alloy wire is used for the steelmaking production process of the low alloy steel, a large number of fine Ti-containing oxides which are dispersively distributed and have the particle size of between 0.5 and 3 mu m can be obtained.