This purpose of the research is discussing the different price limit system, new auction system, and stock repurchases system in Taiwan stock market. Because a company’s value is responded by stock price, changing transaction system of stock market will be able to influence the stock the price which is worthy discussing. In order to make the stock market more efficient, fairer and have clearer information in Taiwan, the different price limit system has launched since 1,962; new auction system has started on July 1, 2002; stock repurchases system has launched in August, 2000. Researching on these systems if influence the investors’ volatility, liquidity and efficiency in Taiwan stock market. this the findings abstract reorganization will be as follows. (1) Different price limit system aspect: it’s helpful to promote investors' transaction willing, the transaction behavior also can be more rational, and can catch the stock price. However, profit making and transaction has not influenced significantly. (2) New auction system aspect: investors can catch the stock price, transaction behavior also can more rationality, and is helpful to promotes investors' transaction willing; However, profit making and transaction has not influenced significantly. (3) Stock repurchases system aspect: except for stock price catching, all can enhance investors' transaction willing, make a profit and the transaction volume all promoted. Also, investor can be more rational when jumping into the stock market. The Taiwan stock market is in steps to be international and the liberal. It should believe that the new transaction systems develop right in a positive way for Taiwan capital market in the future.