Objective Explore the value of APM histochemical stain technique in the diagnosis of amniotic fluid embolism(AFE).Method The pulmonary tissues taken from autopsies performed in 1988～2001 including 19 AFE cases and 3 babies died of amniotic fluid aspiratory pneumonia(positive control),10 women in labor died of other causes(negative control) were sectioned again and stained by APM method and HE method. Comparative statistical research was carried out on findings from the 2 staining methods. Results By APM stain,amniotic fluid elements could be found in all AFE cases and positive control cases as well as some negative control cases.In addition,we found 1 positive case neglected and 1 false negative case of AFE retrospectively.Statistical comparison revealed that APM stain can elevate the detection rates both for keratinized epithelium and mucus.Conclusion APM staining provided possibility of detecting some amniotic fluid elements that was not distinguished by HE stain. The APM stain is helpful and can be used for AFE diagnosis in routine histological examination.