In order to have a little affect on primary users’ transition, the second users have to be switched to another channel by the time the primary users come, therefore, the function of sensing should be attached to cognitive code in cognitive wireless network. The slow-start in TCP of cognitive code, however, is caused by the sensing and switching delay, which slow down transit-rate sharply. In this paper, TCP-CWN was proposed to get rid of the frequently slow-start. The algorithm was simulated in NS2, the experimental result illustrated that the TCP-CWN has better performance improvement than TCP when comes to transition in terms of reducing the influence of spectrum handoff in cognitive wireless network.