Objective　To investigate the application of CUSUM (cumulative sum control chart) curve in cardiac clinical teaching of resident surgeon education. Methods　We chose a surgeon of 10 years work experience of attending the preparation operation of internal mammary artery as control ref-erence (standard group

28 patients) and a resident engaged in professional clinical cardiac work no more than 5 years as group 1

a professional training physician engaged in cardiac surgery clinical work more than 5 years as group 2 and took 40 patients' data respectively from the two groups' prepa-ration of internal mammary artery operation. And then we recorded the postoperative mammary artery flow

internal mammary artery preparation time and adverse events data and made statistics analysis with SPSS 19.0

and CUSUM curve with Matlab R2012b polynomial curve. Results　When the density of operate interval and the operate numbers came to about 25 cases

the polynomial curve's slope rate went up to 0

regardless the surgeons' experience

CUSUM value was accumulated from 66 to 76

and overcame the learning curve successfully. However

when the density of operate interval did no reach the standard

the surgeon's CUSUM ploynomial curve slope rate never reached to 0

and can't over-come the learning curve. Conclusion CUSUM curve gives a clear quantitative indicator to the culti-vation of clinical physician

and makes teaching teachers can understand the young physicians' learning process

so as to change the teaching plan

help young physicians cross the learning curve as soon as possible.