Students inevitably encounter problems that they cannot solve independently in the process of learning. This is especially true for primary school students, whose learning ability is not fully developed. Educational psychologists believe that academic help-seeking, an adaptive self-regulation strategy that can make comprehensive use of human resources in the classroom, is important to students’ academic development and personal growth. However, shy individuals may feel too embarrassed to communicate with others, and a timid personality may be a key reason why some primary school students avoid academic help-seeking. The present study introduced personality-variable shyness to examine the relationship between shyness and academic help-seeking and further explore the roles of self-esteem and the classroom environment to enrich theoretical research on academic help-seeking. Through convenience cluster sampling, 936 students in the fourth, fifth, and sixth grades from two primary schools in Jinan were selected as participants. The shyness scale, self-esteem scale, classroom environment scale, and academic help-seeking behavior scale were adopted as research tools to shed light on the current status of academic help-seeking among students at these schools in middle and upper grades and its relationship with shyness, self-esteem, and the class environment. The results revealed the following. (1) Shyness can positively predict executive help-seeking and avoidant help-seeking behavior (β = 0.30, p < 0.001, β = 0.44, p < 0.001) and negatively predict instrumental help-seeking behavior (teachers/classmates) (β = ?0.27, p < 0.001, β = ?0.10, p < 0.01). (2) Self-esteem mediates the relationships between shyness and executive help-seeking, avoidant help-seeking, and instrumental help-seeking behavior (teachers/classmates). (3) The classroom environment moderates the relationships between shyness and self-esteem and between self-esteem and instrumental help-seeking behavior (teachers). By utilizing simple slope analysis, we found that shyness predicts self-esteem slightly better in a good classroom environment than in a bad classroom environment. Regardless of the degree of shyness, the level of self-esteem in a good classroom environment is significantly higher than in a bad classroom environment. Additionally, the positive predictive effect of self-esteem on instrumental help-seeking (teachers) is more significant in a bad classroom environment than in a good classroom environment. Regardless of the degree of self-esteem, instrumental help-seeking (teachers) in a good classroom environment is significantly higher than is instrumental help-seeking (teachers) in a bad classroom environment. The study helps to fill the research regarding the impact mechanism of shyness on academic help-seeking and explores the impact mechanism of shyness on academic help-seeking from both internal and external perspectives. The results indicated that shy pupils use more negative academic help-seeking, driven largely by low self-esteem. It was also revealed that self-esteem is a powerful factor affecting individual behavioral patterns and that the development of self-esteem is closely related to both family and school education. Overall, our results offer targeted education advice for parents and school educators. In addition, a good classroom environment helps primary school students to actively seek help. In other words, personal growth and the classroom environment are inextricably linked, with the classroom environment shaping personal qualities and behavioral patterns. This conclusion will hopefully serve as a reminder for educators to pay attention to shy primary school students, foster a good classroom environment, work to enhance their students’ self-esteem, and guide their students to form positive academic help-seeking strategies.