We report on the experimental realization of a standing-wave atom tweezer (SWAT) by aligning tightly focused dipole laser beams from a commercial objective lens and a metalens on a chip. By independently tuning the laser intensities of the two beams, we demonstrate the controlled loading of multiple atoms into the SWAT. We systematically investigate the influence of the standing-wave potential modulation depth on single-atom loading dynamics and quantitatively estimate the number of atoms in the SWAT by calculating the fluorescence of trapped atoms. Our results show that the SWAT can trap a chain of more than 20 atoms with significantly suppressed atom collisions, exhibiting a lifetime exceeding 1 second. Our work presents a versatile platform for investigating atom dynamics in 1D optical lattices, enabling the study of collective atom-photon interactions and many-body physics in a highly controllable system.