本文就《河上公注老》之作，討論其哲學體系建構中之方法論問題，首先指出，《河注》將老子道概念的本體義涵轉向宇宙始源義的道概念，是一個將本體論問題意識向宇宙論問題意識的轉化，其所提之長生久壽之修練哲學是一個宇宙論進路的功夫哲學，並且這一個長生久壽之學尚非為長生不死之學，因為體系中還沒有足夠的理論建構以作為追求長生不死的知識依據。《河注》中提出治身即治國之觀念，則是一個從社會哲學到形上學的理論接泊問題，是以老子無為本體為治國原理，以《河注》之宇宙論進路的功夫哲學言治身，最後論及河注中對鬼神概念的使用尚未進至建立鬼神存在的知識，因此都還談不上為神仙修鍊哲學建立理論。文中亦提出哲學體系研究法，作為研究個別哲學家的理論研究法，透過對理論型態的整體定位，以確定個別哲學家的哲學體系在哲學史上的理論地位。

　　　　　This paper focuses on the methodology embedded in the philosophical system of He-shang-gung's Annotations of Lao Zi, pointing out first that it changes Lao Zi's substantial idea of Tao into the cosmologic sense of Tao, making an ontological question into a cosmological issue. The philosophy of longevity mentioned in the book is a cosmological philosophy rather than one of amrita, since the theory is not well grounded enough to be the intellectual foundation of amrita. The book also argues that personal cultivation is just like the governance of the state, connecting the issue of social philosophy with the issue of metaphysics, building the principle of state governance on Lao Zi's idea of do-nothingism, seeing the cosmology in the book as a way to cultivate oneself. Finally the author argues that the ideas about demons and deities in the book can't constitute the ontology of demons and deities yet, let alone the philosophy of divine cultivation. This paper also refers to the question about how to study a philosophical system s the methodlogy of studying different philosophers. Determining the status of the theories, we can decide the importance of a philosopher's system in the history of philosophy.