電火花線切割機按走絲速度可分為高速往復走絲電火花線切割機(Reciprocating type High Speed Wire cut Electrical Discharge Machining俗稱“快走絲”)、低速單向走絲電火花線切割機(Low Speed one-way walk Wire cut Electrical Discharge Machining俗稱“慢走絲”)和立式自旋轉電火花線切割機(Vertical Wire Electrical Discharge Machining machine tool With Rotation Wire)三類。高速走絲與低速走絲(或快走絲和慢走絲)的提法，是用電極絲的走絲速度來區分的。