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M-type stars, with masses ranging from approximately 0.01 to 0.5 Msun, are the most common stars in our galaxy, accounting for about 70% of the total stellar population. They serve as intriguing laboratories for investigating planet formation in extreme conditions characterized by low temperatures and densities. This interest arises from the observed higher frequency of Earth-sized planets in habitable zones around M-stars, as exemplified by notable cases like the TRAPPIST-1 system and Proxima Centauri b. Meanwhile, the population of giant planets around M-stars is less than a few percent of the detected exoplanets so far. The trends of exoplanet demographics may be reflected in the properties of the birth places of planets, a.k.a., protoplanetary disks, around M-stars. In the talk, I will review recent high-angular resolution ALMA observations of protoplanetary disks around M-stars, particularly very-low-mass stars with approximately 0.1 to 0.2 Msun.