The present invention relates to a diet food manufacturing method using egg white that increases the income of poultry farmers who have reached the limit of increase in sales and is in the spotlight as diet food, and in more detail, has an excellent taste of barbecue due to the smell of charcoal. It relates to a method for preparing diet food that has excellent texture and taste even for direct ingestion, and is very useful for preparing salads, etc. along with other foods.The present invention provides a) egg yolk (yolk) and separated egg white (white). Homogeneous steering (stirring) step: b) Putting the egg white of step a) in a container with a sieve of 50 to 250 mesh at the bottom and applying pressure from the top to collect the egg white flowing through the hole of the sieve : c) filling the container with the egg white of step b) and sealing the mouth of the container so that moisture does not enter: and d) putting the container filled with the egg white of step c) into water at 60 to 80°C and adding the egg white It provides a diet food manufacturing method using egg white, characterized in that it comprises the step of cooking.