Abstract: The epitaxial strain effects and Born effective charge of the cubic LaAlO₃ (LAO) are investigated, using the first-principle based on density functional theory. From the results of the density of states (DOS) Mulliken distributions of LAO, the La-d, Al-s, p and O-p are predominant role of orbital electrons, and Al-O orbital hybridization effect is of relatively large. Under the stress-strain in the lattice interface, the potential well curve of LAO shows single well and is different to the traditional ferroelectric double well curve. The energy change of the relative displacement of Al atomic also shows that ferroelectric distortion of LAO in the ground state is very weak or not. The analysis of the Born effective charge shows that the Al-O orbital hybridization effect (charge transfer) did not reach the energy required for the ferroelectric distortion, leaving the LAO no ferroelectricity.