The present work deals with the spatial distribution of the sciarid species (black fungus gnats) recorded from Morocco throughout the major biogeographical regions: Rif, Eastern Morocco, Atlantic Plain, Middle Atlas, High Atlas, and Anti-Atlas, providing for the first time an atlas of the distribution of Moroccan sciarid fauna. The analysis of the species distribution showed differences between the regions, revealing that the High Atlas and the Rif hosted the greatest specific richness. Of the surveyed sites, forests, crop fields, and aquatic habitats seem to be the most favourable for supporting many sciarid species. Ecological preferences for each species are discussed, indicating a clear preference for medium altitudes ranging from 500 to 1000 m. Alongside the study on the distribution of species, a review of the species recorded in Morocco and gathered from the literature has enabled us to update the checklist of sciarid species, which comprises 65 so far in Morocco. Particular emphasis focused on black fungus gnats considered potentially harmful, with the aim of assessing their distribution in the country, has revealed that Bradysia transitata, B. trivittata, B. xenoreflexa, Lycoriella sativae, Scatopsciara subarmata were collected from strawberry greenhouses (Rosaceae: strawberries), Bradysia placida, B. santorina, B. scabricornis, B. tilicola, B. trivittata and Camptochaeta jeskei were collected from fruit trees (Rosaceae: almond trees), Bradysia santorina, Corynoptera saccata and C. semipedestris were found on palms (Arecaceae: date palms), Scatopsciara atomaria and S. curvilinea were captured in crop fields (Poaceae, Fabaceae), Bradysia scabricornis, Bradysiopsis vittata were collected from Liliaceae, Scatopsciara atomaria was also found on Asteraceae and Solanaceae, and Corynoptera praeparvula was exclusively reported from Solanaceae.