Organic crystals constructed by pi-conjugated molecules have been paid great attention in the field of organic optoelectronic materials.The superiorities of these organic crystal materials,such as high thermal stability,highly ordered structure,and high carrier mobility over the amorphous thin film materials,make them attractive candidates for optoelectronic devices.Single crystal with definite structure provides a model to investigate the basic interactions between the molecules (supramolecular interaction),and the relationship between molecular stacking modes and optoelectronic performance (luminescence and carrier mobility).Through modulating molecular arrangement in organic crystal,the luminescence efficiency of organic crystal has exceeded 80% and carrier mobility has been up to the level of 10 cm2/Vs.Amplified stimulated emission phenomena have been observed in many crystals.