Shyness is a normal psychological phenomenon, innate qualities play a big role. Some people are introverted, speak in a low voice, blush when they see a stranger, and often harbor a timid mentality. At the same time, education is also a cause of shyness, in early childhood did not get good guidance, to adolescence, with the gradual maturation of self-awareness, so that adolescents are sensitive to the evaluation of others on their own, become timid, formal. Lack of self-confidence is another reason. Some people always think that they do not have attractive appearance, do not have the ability to be a mediocre person. This situation not only makes them not experience the joy of success for a long time, but also more distrust of their own abilities. The cognitive bias of underestimating oneself is often the most important acquired cause of shyness. In addition, the experience of frustration can also lead to shyness. According to statistics, about 1/4 of shy adults were not shy as children; such people used to be cheerful and generous and had active interactions, but they became timid and passive because they had been frustrated in their academic life. Although shyness is a normal psychological phenomenon, but if a person is shy on any occasion with people, or even afraid or unwilling to interact with people, it will affect the normal interpersonal relationships. People with shyness often show characteristics of shyness, squirming, unnatural, blushing, low volume of speech, etc. People with serious shyness even shy away from interaction and take an avoiding attitude towards interaction. The direct harm of shyness as a psychological disorder to college students is that it prevents them from expressing their feelings, which often leads to the lack of understanding or misunderstanding between the two parties and makes the interaction end in failure; its indirect harm is that it leads to the negative changes in the emotion and character of the interactor, causing frustration, anxiety and loneliness after the interaction, which in turn leads to weakness, retreat and indifference.