A 3 years survey was conducted from 2011 to 2014 during which 133 Agaricus-like mushrooms from different places in primary forests, fields and gardens of the University of Dar es Salaam, Mwalimu JK Nyerere Mlimani Campus were collected. Agaricus-like mushrooms are morphologically characterized by medium to large size basidiocarp on the central stalk that separates easily from the cap, free gills, presence of veil and chocolate brown basidiospores in mature specimens. Characterizing them using both macro-micromorphological features and molecular markers (ITS sequences), they were revealed to be 12 species belonging to two distinct genera Agaricus L. and Hymenagaricus H. The species Agaricus xanthodermus and one un-described were suspected poisonous, edibility of 3 species were known while the edibility of the rest were unknown. Based on the result finding, one Hymenagaricus and two Agaricus species are also proposed as novel species for scientific descriptions based on International Code of Nomenclature.