Abstract: In the daily microstructure testing, there are always some similar microstructures in both color and shape in the disequilibrium microstructures of steels, and they are difficult to be identified by the new learners. With the commonly used irons and steels as examples, by careful comparison of the microstructure shape, distribution and color with the optical microscope combined with analyzing the heat treatment process, the identification methods between ferrite and retained austenite, carbide and retained austenite, low-carbon lath martensite and featherlike upper bainite, and needlelike martensite and needlelike lower bainite were summarized to provide reference to the metallographic workers.