最近一個時期來，中外學術界對東方的兩大宗教 -- 密教與道教表現出了強烈的 興趣，進行了廣泛深入的研究和討論，參加討論的不僅有宗教學者、佛教或印度教研究家， 而且還有不少的化學家、物理學家、歷史學家和社會學家等。密教和道教之所以引起人們的 重視主要因為這兩個宗教都是傳統宗教，在南亞和東亞地區有著廣泛的影響，特別是他們的 化學和醫藥學思想在歷史發展過程中曾經起過一定的作用，而且他們的某些哲學觀點對現代 的量子力學和生理學還有借鑒意義。密教和道教雖然是印度和中國的民族宗教，但是這兩個 宗教有著長期的交流的歷史，無論在教義和修持實踐方面有著很多的相似之處。不少學者認 為，印度的密教淵源於中國的道教，也有人持相反的看法。本文擬根據中印各自保存的歷史 資料，對密教和道教的關係作一粗略的試探。

　　　　　In recent years, scholars in China and abroad have expressed a strong interest in Taoism and Tantrism, engaging in extensive research and discussion of these two great religions. These discussions have not been limited to specialists in religious studies, Buddhism and Hinduism, but have included as well chemists, physicists, historians and sociologists. The main source of this interest is that both Taoism and Tantrism are traditional religions with great influence in South and Southeast Asia. In particular, the two religions played an important role in the historical development of chemistry and medicine in their respective cultures. In addition, some have seen in the doctrines of Taoism and Tantrism implications for quantum mechanics and physiology. Although Tantrism and Taoism are religions of, respectively, the Indian and Chinese people, the two religions have a long history of exchange, and share similiarities in doctrine and practice. Many scholars maintain that the Tantrism of India originated in Chinese Taoism. Others hold the opposite view. In this article, I present a rough sketch of the relationship between Tantrism and Taoism based on extant materials from China and India.