⽬的：傳統的觀察性研究表明飲食因素與前列腺癌（PCa）之間存在聯繫，但混雜因素對這種關聯的影響仍不確定。本研究旨在利⽤孟德爾隨機化⽅法（MR）調查飲食與 PCa 之間的潛在因果關係。⽅法：我們使⽤雙樣本 MR ⽅法研究了飲食因素與 PCa 之間的潛在因果關係。本研究從英國⽣物銀⾏和 FinnGen 數據庫中提取的有關飲食因素和 PCa 的全基因組關聯研究（GWAS）的總體統計數據。我們使⽤了六種不同的 MR 分析⽅法探討飲食因素與 PCa 之間的相關性。主要分析⽅法為逆⽅差加權法（IVW）。同時，我們使⽤MR-Egger 回歸、Cochran's Q 檢驗和 MR-PRESSO 檢驗和留⼀法來評估 MR 結果的穩健性。結果：本研究結果顯⽰，平均每週啤酒加蘋果酒攝入量（OR=3.305，p=0.040）和油性⿂攝入量（OR=1.877，p=0.012）與罹患 PCa 的可能性增加相關，⽽綠茶攝入量與 PCa 風險呈負相關（OR=0.985，p=0.014）。本研究中其他飲食因素與 PCa 之間沒有顯著的直接因果關係。結論：本研究發現，增加平均每週啤酒加蘋果酒攝入量和油性⿂攝入量可能會增加 PCa 的風險，⽽增加綠茶攝入量可能會降低 PCa 的風險。本研究結果可為公共衛⽣及護理領域優化飲食⼲預措施提供參考，助⼒前列腺癌的預防⼯作。

Objective: Conventional observational research has indicated a link between dietary factors and prostate cancer (PCa), yet the impact of confounding factors on this association remains uncertain. The aim of this study was to investigate the potential causal relationship between dietary factors and PCa using the Mendelian randomization (MR) approach. Methods: We examined the potential causal association between dietary factors and PCa by employing a two-sample MR approach. In this study, summary statistics from genome-wide association studies (GWAS) on dietary factors and PCa were extracted from the UK Biobank and FinnGen databases. Six different MR analysis methods were employed to explore the correlation between dietary factors and PCa. The main analytical method is the inverse variance weighted (IVW) method. Meanwhile, we used MREgger regression, Cochran's Q test, the MR-Pleiotropy RESidual Sum and Outlier (MR-PRESSO) test, and the leave-one-out method to assess the robustness of the MR results. Results: The results of this study showed that the average weekly beer plus cider intake (OR=3.305, p=0.040) and oily fish intake (OR=1.877, p=0.012) were correlated with an increased likelihood of developing PCa, while green tea intake was negatively associated with the risk of PCa (OR=0.985, p=0.014). There was no significant direct causal relationship between other dietary factors and PCa in this study. Conclusion: This study found that increasing the average weekly beer plus cider intake and oily fish intake may increase the risk of PCa, while increasing green tea intake may reduce the risk of PCa. The results of this study can provide a reference for optimizing dietary intervention measures in the fields of public health and nursing and assist in the prevention of PCa.