The effect of in-situ magnetic field during deposition (dynamic aurora PLD) was examined for SrTiO3 thin film deposited on (La0.5Sr0.5)CoO3/CeO2 buffered YSZ(001) substrates. It was found that both in-plane and out-of-plane lattice parameters were changed by the in-situ magnetic field. Reciprocal space map measurement revealed that the in-plane and out-of-plane lattice parameters are 0.3817 and 0.3953 nm without magnetic field, meanwhile those are 0.3906 and 0.3974 nm with magnetic fields of 2 kG. This indicates that biaxial strain induced by the magnetic field. The effect of magnetic fields on the ferroelectric properties was examined.