This research focuses on revealing the effect of size and shape of Ag particles for mechanical properties of no-pressure sintered Ag by using micro-compression test. Specimens were fabricated by focused ion beam with the dimension of 5 μm × 5 μm × 15 μm. The stress-strain curve suggested that the sintered Ag subjected a stable elastic deformation and a large plastic deformation. The mechanical properties of sintered Ag such as elastic modulus, and yielding stress, were evaluated, which strongly depend on the size and shape of used Ag particles. In addition, with the evaluation of shear strength for the various sintered Ag particles, it was found that sintered Ag with Ag nanoparticles has a low elastic modulus and low bonding quality due to many voids formation during the sintering process. In addition, sintered Ag micro flake shows the shear strength over 30 MPa in no-pressure sintering condition. The value was far larger than the shear strength of sintered Ag using Ag particles with spherical shape. These results will be helpful to understand from a technological perspective for reliable applications of sintered Ag and a fundamental interest in understanding its mechanical properties with different size and shape of Ag particles.