The invention relates to an identity information analysis method which includes the following steps: pre-storing voice information of each waiter/waitress in a restaurant and reference voice information; receiving the historical dining time of each customer, and getting customer frequent dining time periods based on the historical dining time of each customer; collecting restaurant ambient sound in real time, and analyzing the real-time collection result to determine whether the restaurant ambient sound collected in real time contains customer voice; and receiving a customer frequent dining time period, and giving out a service preparation signal if the current time falls into the customer frequent dining time period and the restaurant ambient sound collected in real time contains customer voice.