The present invention provides non-small cell lung cancer markers and the use thereof in diagnosing and monitoring diseases in vitro. The non-small cell lung cancer markers include at least one of the 26 selected detectable mature microRNAs existing stably in human serum or plasma. The invention also provides probe combinations, a kit and biochip for detecting the non-small cell lung cancer markers. The invention further provides a method for detecting the said lung cancer markers. The method in the present invention enables extensive detection spectrum, high sensitivity, low cost, convenient sample taking and preservation. The method can be applied in the general survey of disease, solves problems of the low specificity and sensitivity encountered with previous single markers, and increases significantly the clinical detection rate of diseases; it forms an effective means for diagnosing diseases at an early stage.