本文透過有限元素軟體Deform-3D進行旋轉鍛造螺旋傘形齒輪模擬分析,探討加工參數以及胚料幾何參數對鍛造最大成形力以及填充率的影響,並找出最合適之加工條件,達到提升填充率及降低成形力的目的。本文設計之旋轉鍛造加工參數包含下模具每轉進給量S以及上模具傾斜角γ;胚料幾何參數包含胚料中段直徑D及胚料高度H。實驗設計採用Box-Behnken四因子三水準設計,以建構二階反應曲面。本文共建立25組實驗點進行模擬分析,其中包含一組中心點實驗,再使用統計軟體Minitab對模擬結果進行回歸分析,建立最大成形力以及填充率之預測模型,進而探討各因子對品質特性的影響,並找出最佳化條件。以有限元素模擬結果對本文所建構之預測模型進行檢驗,其結果顯示預測模型具有一定的準確度。;An FEM model of cold rotary forging of a spiral bevel gear is developed under the DEFORM-3D software. To observe the influence of work-piece geometry parameters and rotary forging process parameters to the forging maximum load and die-filling rate. Also, intend to find the rotary forging condition for optimum design. The four factors in the design include the work-piece geometry parameters, such as height H and middle diameter D, and rotary forging process parameters, such as inclination angle of the upper die γ and feed amount of per revolution S. The experiment adopts 25 groups of analogs with the Box-Behnken design. Using the Minitab software to do the regression analysis and develop the prediction equations. Obtaining the optimum design of the forging maximum load and die-filling rate by using response surface methodology. Through the results of FEM simulations to verify the prediction equations with considerable accuracy.