During the last years of the Chin Dynasty and the early years of the Republic of China (1895-1928), how did the YMCA, a foreign religion group, struggle to develop its physical education careers and end up mastering the modern times Chinese physical education development, especially in China, a severe circumstance which has its overwhelming traditional superiority both in racial and cultural. For inquiry the causes, the author has obtained following conclusions by collecting and analyzing enormous historical records and documents: 1.The time background of “utilize foreign advantages to fight them back”, and the moment of “save the country from destructions”, made felicitous conditions for YMCA to develop and carry on its physical education careers. 2.Strict organizational structures ensured the YMCA to develop its physical education careers substantively and in a highly efficient way. 3.Outstanding human resources, settled a firm foundation for future prosperity of the YMCA physical education careers. 4.Healthy relationships with the political authorities, made free and favorable circumstances for the expansions of the YMCA careers.