It has been found that poly(styrene-block-butadiene-block-styrene) (SBS) forms a regular structure and the structure transforms into another regular structure at the interface with poly(xylenyl ether) (PXE). This study examines the order-order transition phenomena with a transition electron microscopy (TEM) and an atomic force microscopy (AFM). According to TEM observations, the thickness of the morphological transition area depends on a temperature and time. In some cases, the thickness of the new regular structure's area could reach 1000 nm. Such phenomena have not been reported yet. A layer of which viscoelasticity changes continuously is observed at the interface of PXE and SBS with an atomic force microscopy (AFM), and the thickness of the layer is almost same as the thickness of the morphology transition layer observed with TEM.