By taking a model that hadrons are confined composite systems of the urbaryon q linked by the string, possible roles of a three-string junction J in hadron reactions are examined. The junction brings about new patterns to the conventional urbaryon rearrangement diagram. The leading behaviour of BB annihilation cross section is naturally explained by the exchange of one junction pair (JJ). The Regge intercept is related to the number of the exchanged q and J, satisfying the sum rule αP(0)+αB(0)=2αM(0). The rearrangement diagram of q and J divides exotic exchange amplitude into two classes, one with rather slow s dependence and the other with rapid one, in agreement with experiment. In addition to the pole-pole type duality, a new type of duality (pole-cut) is expected for some components of BB amplitude. Both of q and J carrying four momentum lead to a successful counting rule at large momentum transfers.