本研究以Ajzen的計劃行為理論（the Theory of Planned Behavior）為依據，主要目的在了解本研究對象每日飲用牛奶的意圖，行為有其影響因素。同時並比較理性行動理論（the Theory of Reasoned Action）與計劃行為理論兩者應用每日飲用牛奶的適切性。
本研究以私立醒吾商專日間部（五專）一至四年級全體學生為母群體，以分層集束抽樣法法抽出調查樣本進行施測。研究者依據開放式引導問卷填答結果篩選出顯著信念，編製而成正式問卷，一個月後以電話訪問方式追蹤行為。共得到805份有效問卷，行為追蹤則完成796人。
本研究結果如下：
一、本研究對象每日飲用牛奶的行為可以由意圖和知覺行為控制來預測，並且意圖與知覺行為控制之間具交互作用。
二、飲用牛奶的意圖是受到態度，主觀規範，知覺行為控制三者的影響，三者可以解釋意圖61%的變異量。
三、態度與行為信念、結果評價的交乘積和呈中等程度正相關；主觀規範與規範信念、依從動機的交乘積和呈中等程度正相關；知覺行為控制與控制信念之間也呈中等程度正相關。
四、有／無意圖者在行為信念，結果評價，規範信念，依從動機及控制信念上有整體上的差異。
五、過去飲用牛級的習直接影響每日飲用牛奶的行為，具相當大的影響力。外在變項可直接影響意圖，但影響力不大。
整體而言，本研究結果支持計劃行為理論的假設，並發現計劃行為理論應用在每日飲用牛奶行為上的適切性大於理性行動理論。

The purpose of this study was to predict and to explain the students' intentions nad beahvior of daily drinking milk in junior college by using the Ajzen's Theory of Planned Behavior(TOPB), and to compare the Theory of Reasoned Action (TORA) with TOPB in terms of predictiove validity.
The population of interset was students from the first to the foutrh grade classes in the Hsing-Wu Junior College. By stratified clusted sampling method, 805 respondents (96% response rate) were selected to participate in this study. Data were colected by open-questionnaire, structured questionnailre, Data were colected by open-questionnaire, structured questionnaire, and follow-up telephone interviews. The main findings of this study were: (1)Both of the preceived behavioral control and intentio could be used to predict the subjects' behavior in daioy drinking milk, and having the significant interaction between preceived behavioral control and interntion. (2)The intention to daily drinking milk could be predicted by attitude, subjective norm, and preceived behavioral control and the explained variance was 61%. (3)The sum of products in terms of behavioral belief multiplying evaluation had moderately positive correlation with the attitude; the sum of products in terms of normative beliefs multiplying motivation to comply and moderately positive correlation with the subjective norm; adn the perceived behavioral control and moderately positive correlation with the control belidfs. (4)Whether there was intention to drink milk or not was shown to differ significantly in behavior belief, evaluation, normative belief, motivation to comply, and control belief. (5)The past milk drinking habit having significant effect on the current milk drinking pattern, and external varialbes having minor effect, both were in contradiction with the assumption.
The result of this study supported the hypothsis of the TOPB and revealed that the TOPB was more feasible than TORA on explaining the intentions and behavior to daily drinking milk Implications for use of this knowledge by helth educators in develiping relevant interventions to enhance the rate of daily drinking milk are discussed.