In temperature range of 20K to 300K, we measuded photoluminescence spectra of heterogeneous J-aggregate Langmiur-Blodgett (LB) films made of three kinds of cyanine dye. With temperature reduced, while the intensity of J-peak, the zero phonon line increased, anomalous enhancement of the phonon sideband was observed. Analysis shows that J-aggregatc LB films are of characteristics like that of low dimensional crystal, they have strong phonon coupling, and nonradiative transition plays important role.