The solidification test of 60Cr13 martensitic stainless steel was carried out by laser confocal microscope at the cooling rate of 5-60 ℃/min， and the secondary dendrite spacing and carbide precipitation morphology were observed by metallographic microscope， the area ratio of eutectic letensite was measured by image processing software. The results show that different from the thermodynamic equilibrium state calculated by Thermo-Calc， no ferritic phase is found to precipitate in the liquid phase during the solidification process， and then the peritectic reaction between the ferrite phase and the liquid phase form austenite phase. Instead， the austenite phase is precipitated directly from the liquid phase， and the rich solute liquid phase is excreted as the austenite gradually grew. Eutectic transformation occurs in the rich solute liquid phase to form Letenite. The secondary dendrite spacing is related to the cooling rate by

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. In addition， with the increase of cooling rate， the size and quantity of eutectic letenite decrease gradually， and the overall area proportion decreases gradually.