Abstract: OBJECTIVE To discuss the influence of dabigatran etexilate on coagulation function and the significance of anticoagulant activity monitoring. METHODS The clinical pharmacist put forward some reasonable drug treatment suggestions according to the coagulation indexes of dabigatran etexilate in a patient with pulmonary embolism. RESULTS The patient with activated partial thromboplastin time (APTT) prolonged more than 2 times of the upper limit of normal (ULN), and clinical pharmacist suggested the APTT should be re-examined 12 h after the last dose and target value was 1.5 times of ULN, and the target was met after the re-examination. CONCLUSION Routine coagulation tests can help determine anticoagulant effect in specific populations and the timing of blood sampling is very critical. The APTT may provide a qualitative assessment but the results need to carefully interpretate.