The paper provides an overview of the Mizarai impact structure located in southern Lithuania, discovered in the course of geological mapping in 1969 and identified in 1975. Since then, the structure has been investigated by the mapping of gravity and magnetic fields, 2D and 3D seismic surveys, drilling and core studies. The structure is in the form of an oval depression situated within the Precambrian crystalline basement filled with presumably Ediacaran to Lower Cambrian detrital sediments derived from target rocks and ejecta and overlined with Mesozoic and Quaternary sediments. Gravity and seismic data have not indicated the presence of a central uplift within the Mizarai depression, suggesting a simple form. We estimate that the recent size of the crater is 3.8 × 4.2 km, after erosion in the course of ~ 300 Ma. Before erosion, the primary crater had a rim-to-rim diameter of up to 5 km and a depth of approximately 1 km. The impact metamorphism manifested in the transformation of target rocks into impact breccias and impact melt rocks, displaying shock features such as shatter cones, isotropization of quartz and plagioclase, planar deformation features (PDFs) in quartz, and kink-bands in biotite. While most impactites reflect the target rock composition, suevitic impact breccias and impact melt rocks (glass) are enriched by potassium.