Abstarct: Nowadays increasing transportation, causes finding solutions for improving traffic is more vital. Among the used strategies for resolving traffic problem, using of traffic light in roundabout is more efficient and also despite high utilization of signalized roundabout in Iran, no more detailed studies on deriver behavior on signalized roundabout have been performed. The purpose of this study is to determine the length of type II dilemma zone (type II DZ) in signalized roundabouts baxsed on indicators like distance and time to stop line (DTS and TTS) dependent on the changes occur in driver’s behavior and attitudes. Investigation of am, as and δs that effects on type II DZ, determination of all-red interval baxsed on kinematic moving vehicles and time to collision (TTC) and determination of stopping probability of Logit regression are other purposes of this study. The results confirmed that TTS is more appropriate in determining the length and position of dilemma zone compared to DTS in which the DZ is very long. In this study, the proposed length of dilemma zone (DZ) equals 1/5 to 4/5 second from stop line. A significant match and unity was shown among the concentration and variance indicators of the perception reaction time (δs) of drivers of this study and the previous ones. But such unity was not observed for acceleration (am) & deceleration (as) behaviors. The deceleration (as) of first to stop (FTS) cars equals 1/26 m/s2 ,the value of which is about one-third of the one proposed by ITE and AASTHO. The drivers drive more cautiously in signalized roundabouts than signalized interactions. The results about stopping probability showed among type of vehicles in this study, heavy trucks/buses were more effective on stopping probability. On other factors speed, DTS, TTS are effective on stopping probability and yellow interval is not effective on stopping probability.