With the emphasis on teacher expertise to improve the quality of public education, this study analyzed whether teachers had a significant influence on enhancing students educational aspirations and whether their influence decreased or increased in the mid-2010s, compared to the mid-2000s. By pooling the data from the base year of the Korea Education Employment Panel I (KEEP I; 2004) and the data from the base year of KEEP II (2016), the relationship between educational aspirations and student perceptions of teachers as significant influencers was analyzed, employing multinomial logistic regression methods. The results of the analysis are as follows: First, the degree of recognition of teachers as significant others was significantly lower in 2016 than in 2004. Second, teachers did not significantly boost educational aspirations among students who did not have college plans. Third, teacher influence showed a statistical significance in increasing the likelihood of students aspirations for graduate studies. Fourth, the degree of teacher influence on increasing the aspirations of students for graduate studies was lower in 2016 compared to 2004. Based on these findings, implications are discussed.