The stress states are measured for hot wind furnace of balst in working and reliable data are supplied for safety operation. Dispalcements and strains of shell of hot wind furnace are measured by digital speckle correlation method (DSCM) in real time.Simultaneously, mark point method is also adopted for measuring the displacements and strains of hot wind furnace shell in order to compare the results obtained by DSCM. In the experiment, displacements and strains of circular and axial direction for furnace shell are obtained successfully. And the results obtained by DSCM and mark point method agree well. Through on-the-spot test, it can be concluded that the working stresses are lower than permissible stresses under different working states for hot wind furnace. So the operation of the hot wind furnace is safety.