隨著網路普及，有越來越多的虛擬社群開始分享使用各種產品的心得，消費者在購買前也會根據網友的分享資訊，再進行產品採購，因此這些分享資訊就成為相當重要的採購資訊。如果能夠將這些購買資訊加以整理，並以知識化概念呈現，將可以了解消費者對於美妝產品購買資訊的關聯程度，並協助廠商了解消費者相關行為。研究利用系統抽樣的方式抽取美妝YouTuber影片中的留言，共蒐集有效樣本2479筆，並用正規化概念分析整理出內容包含「產品名稱」、「產品品質」、「價格」、「購買地點」、「產品特色」、「使用情況」六種購買資訊之知識概念圖。研究結果顯示，除了「產品名稱」在留言時經常被提起外，「產品特色」和「使用情況」的資訊也經常被社群成員提出來分享。另外，本研究進一步進行消費者的認知失調研究，結果顯示最容易造成社群成員的認知失調起因為化妝成果，因此建議管理者可以加強將產品試用成果展示內容，以降低消費者的認知失調。

With the e-commerce expansion, people love to share and read purchase experience in virtual community. Those shared reviews become important resource of purchase information. If the information can be constructed by conceptual knowledge structure, it might help to understand consumers' perception and behavior toward purchase information. This study extracted discussion content from YouTubers’ channels and collected a total of 2,479 valid samples by systematic sampling. The knowledge structure of purchase information was produced into six classified items by formal concept analysis, including “Product Name”, “Product Quality”, “Price”, “Purchase Location”, “Product Features”, and “Usage Conditions”. The result shows that not only the “Product Name” is often mentioned in the comments, but also the items of “Product Features” and “Usage Conditions” are also mentioned frequently by community members. The study also conducts the further studies on cognitive dissonance for those who left purchase message. The findings show that main reason which most easily to cause cognitive dissonance is the “makeup performance”. It is suggested that the pre-test of products should be well presented to reduce the possible cognitive dissonance.