The stress cracking and crack-healing effects in dimethyl phthalate, diethyl phthalate, dibutyl phthalate and dioctyl phthalate series glassy materials was measured by the recently invented method (RMS-L-CH) which measures the stress cracking and crack healing in situ and further analysis and discussions on the crack healing phenomenon as well as its relation to the glass transition are presented. The results validate that the RMS-L-CH method is effective and may provide a new means to characterize the glass transition and to probe into the glass transition mechanism.