Objective To investigate the expression of N6-methyladenosine (m6A) binding protein hnRNPA2B1 in various tumors and its relationship with prognosis and immune infiltration. Methods We investigated the expression of hnRNPA2B1 in different tumors and verified it in gastric cancer (GC) tissue microarray using immunohistochemistry. Univariate COX regression and Kaplan-Meier survival analysis were used to identify the prognostic value of hnRNPA2B1 in pan-cancer. In addition, we explored the correlation between the expression of hnRNPA2B1 and immune cell infiltration, immune checkpoint genes, tumor mutational burden (TMB) as well as microsatellite instability (MSI). Results The expression of hnRNPA2B1 was higher in tumor tissues than in corresponding normal tissues in most cancers. In GC tissue microarray, the expression of hnRNPA2B1 in GC tissues was significantly higher than that in paired adjacent normal tissues. High expression of hnRNPA2B1 was significantly associated with poor prognosis in 7 types of tumors. Moreover, the expression of hnRNPA2B1 was positively correlated with immune cell infiltration in a variety of tumors. In addition, hnRNPA2B1 was notably associated with immune checkpoint related genes, TMB and MSI. Conclusion The expression of hnRNPA2B1 is ubiquitously elevated in a variety of tumors and is associated with poor prognosis. Furthermore, hnRNPA2B1 is closely related to the immune cell infiltration and tumor microenvironment.