Laser manipulation and laser trapping techniques were applied to mum sized gel-like wire-type dendrimer (L3PPE130 and L4PPE8) assemblies, which are formed at drying process of their tetrahydrofuran (THF) solution on a glass substrate. Deformation and extension of single gel-like assemblies were demonstrated with irradiation of a focused 1064 nm laser beam by scanning a microscope stage. In repetitive irradiation experiments, contraction and swelling of the gel-like assembly were observed in response to the switch on and off of the laser beam, respectively, and in the case of the L3PPE130 gel-like assembly, fluorescence spectra detected at a focal point changed accompanying the contraction and swelling behavior. This spectral change means molecular aggregates were formed transiently by photon pressure of the focused near-infrared laser beam.