The utility model provides a novel trailer couple system, including two couple devices that the level was arranged, each couple device includes: two relative up -down's host computer positioning seat, the level sets up on the host computer, welds a horizontally guide holder between these two host computer positioning seats, is equipped with a locating hole on this guide holder, two relative up -down's trailer positioning seat, the level sets up on the trailer, with the host computer positioning seat is mutually supported, at each the same position of trailer positioning seat is equipped with a locating hole, one vertical to the location axle, with the three locating hole of the aforesaid cooperation, the upper end with one vertical to the lower extreme of hydro -cylinder be connected, the free bearing on locates the trailer is connected to the upper end of this hydro -cylinder.