Mass Customization is one of the production methods companies try to implement and answer customers’ requirements in a more flexible way. To deliver the favourite products to customers, mass customizers need to have enough knowledge from customers to apply in design manufacturing processes. To achieve this objective, mass customizers have choices to extract knowledge from customers. Traditional methods of information gathering like questionnaires and even online questionnaires have a little knowledge about customers. This paper also investigates richness of communication channels and confirms that voice conversations, video conferences and face to face communications have more richness and therefor more knowledge. The Idea of this paper rises from the question that “how we can use Human-Computer Interactions to help Mass Customization processes”. This paper suggests that mass customization could apply the hidden knowledge from communication with customers and interactions between customers and computers in virtual spaces in its processes and make more favourite choices for customers. We will see that knowledge flow could be started from customers and trough interacting with computers and communicating through e-commerce (internet) could be entered in Mass Customization processes like designing and manufacturing.