3D imaging techniques such as computed tomography, ultrasonography, and magnetic resonance imaging usually combine many scans computationally. Here, we report a 3D imaging approach using an optical-laser diffraction microscope with two different wavelength lasers in the same orientation. A double-layered sample constructed of silica spheres is used for coherent diffraction imaging with two lasers at 543 and 432 nm. The diffraction patterns obtained using a planar detector at a high numerical aperture are projected onto the Ewald spheres. 3D images of the double-layered sample are successfully reconstructed from the two-color spherical diffraction patterns.