As frontiers of technology, electromagnetic cold crucible technology has been applied to melting and forming of reactive metals, refractory and rare metals. The basic theory and the advantages of this technology are introduced. Constructions of cold crucible and electrical parameters effect on the use of cold crucible are discussed. To be more specific, the constructions of cold crucible include numbers and shape of segment, weight of cold crucible and width of slit, and electrical parameters include frequency, voltage and current intensity. Other factors, such as physical properties of the metal, positions of the shield and the induction coil, are also discussed. Research and application of cold crucible technology in the world are overviewed and difficulties in applying this technology are pointed out. Cold crucible technology will be a hopeful and important technique in the 21st century.