Imaging technology at various scales of spatial resolution is crucial for understanding the physiological and morphological complexity of living organisms. The existing imaging technologies fail to facilitate images of a sample at different magnification levels at a given instant of time. We report the detailed design and instrumentation of an optical imaging system, namely, simultaneous multiple-level magnification selective plane illumination microscopy (with an acronym being given as sMx-SPIM), which addresses one of the technological challenges of imaging biological specimens at different magnification levels simultaneously. The simultaneous magnified views assist in perceiving biological activities occurring over a short period, especially in developmental biology, where the time scales (fraction of seconds) are critical. The proposed imaging system comprises one illumination arm and two detection arms, each of which uses a different magnification to attain multiple magnification levels simultaneously and overcomes the time consumption for changing the objective lens. The system is automated for image acquisition using a custom-built assembly of motion stages and external hardware. Experimental studies are carried out using biological specimens such as Daniorerio and Alliumcepa to validate the home-built sMx-SPIM imaging system at an obtainable spatial (axial) resolution of   ∼  3 to 5  μm.