Objective： To investigate the effect of different processed foods on ACE activity， so as to provide data support for screening for foods with antihypertensive effect. Methods： The experiments of water extraction， pepsin hydrolysate and ethanol extraction of 15 kinds of drinks， 5 kinds of nuts and other 8 kinds of processed foods was carried out. The hippuric acid content was detected by high performance liquid chromatography （HPLC）， and their effects on angiotensin converting enzymes（ACE） activity in vitro were determined. Result： Most of ethanol extracts from 5 kinds of nuts and other processed foods promoted ACE activity， but most of their water extracts or pepsin hydrolysate inhibited ACE activity. The beverages containing milk had significant ACE inhibitory activity， while other beverages only weakly affected ACE activity. The pistachio water extract significantly promoted ACE activity. The pepsin hydrolysate of walnut and ham sausage significantly inhibited ACE activity， and the ACE activity was still significantly inhibited after the pepsin hydrolysate of walnut diluted 10 times. Some processed foods might affect blood pressure. In most foods， substances that raise and lower blood pressure may co-exist in the same food. Consumption of milk or walnuts may help to reduce high blood pressure.