Based on high throughput (HTP) density functional theory calculations and topological characterization, we have identified four topologically nontrivial two dimensional (2D) materials out of 641 most stable systems in the 2D materials database. The HTP screening is carried out based on the automated construction of maximally localized Wannier functions followed by explicit calculations of the surface states, where the Wannier centers are evaluated as a further verification of the nontriviality. The electronic structure of such nontrivial materials is discussed in detail together with the features in the crystal structure and relevant orbitals.