Recent publications have presented research showing that WD repeat domain 4 (WDR4) plays a significant role in various kinds of malignant tumours. However, the expression profile of WDR4 is still unspecified, as is its significance in the analysis of human pan-cancer. We conducted an in-depth analysis of three aspects of WDR4 expression patterns from 33 types of cancer and determined the value of WDR4 for prognostic prediction and carcinoma drug resistance prediction. WDR4 was expressed in different cancer cell lines at inconsistent levels. Aberrant expression of WDR4 has been observed in various malignant cancers and is significantly implicated in overall survival outcomes. The expression level of WDR4 is also strongly associated with tumour immunity, such as immune scores and tumour-infiltrating immune cells. The level of WDR4 is related to microsatellite instability and tumour mutation burden in several types of malignancy, and validation studies implied that WDR4-associated terms and pathways are involved in malignancy. We explored the expression level of WDR4 across 33 types of cancer and showed that WDR4 plays a significant role during cancer development. More crucially, WDR4 is associated with immune infiltration, which suggests that WDR4 could be an immunotherapy target in cancers. In summary, our research showed that WDR4 plays a vital role in tumorigenesis and has the potential for to be targeted with treatments.