The meshless Petrov-Galerkin (MLPG) method is developed to analyse general boundary value problems where the electric field and displacement gradients exhibit a size effect. Both the electric intensity vector and strain gradients are considered in the constitutive equations for piezoelectric material. The governing equations are derived by the variational principle. The coupled governing equations are satisfied in a local weak-form on small fictitious subdomains. All field quantities are approximated by the moving least-squares (MLS) scheme.