Active control of molecular orientation in organic thin films is a promising approach to boost the performances of organic semiconductor devices. The simultaneous manipulation of intramolecular and intermolecular weak hydrogen bonds in an n-type organic semiconductor is presented as a new strategy for the realization of horizontal orientation. Here, we developed 1,3,5-triphenyltriazine-based electron-transport materials, referred to as BPyPTZ derivatives, possessing elaborate intramolecular and intermolecular CH···N hydrogen bonds. The X-ray structure of single crystal of B4PyPTZ apparently reveals that intramolecular H-bonds led to a planar molecular framework. Further, we analyzed their molecular orientation in vacuum-deposited films using variable-angle spectroscopic ellipsometry (VASE). We quantified the degree of the orientation using the orientation parameter S, which is 0 when the transition dipole moments of molecules have a completely random orientation, and is −0.5 when they have a completely horizontal orientation. Consequently, B3PyPTZ exhibited a S-value of −0.38; this value is substantially greater than that of the conventional ETL material 1,3,5-tri(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl (TPBI) (S = −0.02) . Then, we employed B3PyPTZ on OLED’s as a electron transport layer (ETL) for fac-tris (2-phenylpyridine) iridium (III) [Ir(ppy)3], a well-known green phosphorescent OLED’s emitter. The device with B3PyPTZ exhibited extremely low operating voltages of 2.11, 2.47, and 2.88 V at luminances of 1, 100, 1000 cd m–2, respectively. At 1000 cd m–2, this device gave a power efficiency of 73.9 lm W–1, current efficiency of 67.7 cd A–1, external quantum efficiency of 18.8%. As we successfully demonstrated, planar molecular orientation can be actively manipulated by the synergetic effect of intramolecular and intermolecular interactions and an installed organic semiconductor layer can deliver performance beyond that expected on the basis of its molecular formula.