Penicillium (from Latin penicillus: paintbrush) is a genus of ascomyceteous fungi that includes:

• Penicillium bilaiae, which is an agricultural inoculant.
• Penicillium camemberti, which is used in the production of Camembert and Brie cheeses.
• Penicillium candida, which is used in making Brie and Camembert.
• Penicillium chrysogenum (previously known as Penicillium notatum), which produces the antibiotic penicillin.
• Penicillium glaucum, which is used in making Gorgonzola cheese.
• Penicillium lacussarmientei
• Penicillium marneffei, a thermally dimorphic species endemic in Southeast Asia, which presents a threat of systemic infection to AIDS patients.
• Penicillium purpurogenum
• Penicillium roqueforti, which is used in making Roquefort, Danish Blue cheese and also recently Gorgonzola.
• Penicillium stoloniferum
• Penicillium verrucosum produces ochratoxin A
• Penicillium viridicatum produces ochratoxin