This paper refers to Ma and Hung(2004) using the amount of the institutional investors to measure the competitions of trading and the order flows of the institutional investors to measure correlations of information. We filter the data on daily basis and divide the data into four groups: high competition and high correlation, high competition and low correlation, low competition and high correlation, and low competition and low correlation. From the measurements of the informed traders¡¦ intraday behavior, we find that in the sample of high competitions of trading, the informed traders trade aggressively to exploit the common private information in the early period; In the middle period, since the common private information has been revealed to the market, the informed traders trade passively to avoid other informed traders knowing his private information; In the later period, the informed trader trade aggressively again to consume their private information before the market close. So, when trading these stocks, uninformed individual investors should avoid entering the market in the early and the later periods because of the high adverse selection cost. Besides, when prior return increases (decreases), the informed traders tend to place buy (sell) orders, indicating the informed traders are momentum traders. Last but not least, we observe in the sample of low competition and low correlation, the foreign investors behave differently in intraday strategy. Given the increasing of prior return, the buy (sell) orders of the foreign investors become passive (aggressive) in the early period, but in the later period, the buy (sell) orders of the foreign investors turn to be more aggressive (passive) with the increasing of prior return. The result may relate to the strategy of proprietary traders. For this reason, when trading these stocks, uninformed individual investors should avoid following the large orders and the momentum strategy in the early period.