Mari Hoshino (星野 真里 Hoshino Mari, born July 27, 1981 in Kamifukuoka, Saitama) is a Japanese actress and singer. She graduated from Aoyama Gakuin University with a degree in Franch Literature.

Most well-known for her lead role as Otome Sakamoto in T.B.S. drama, Kinpachi-sensei, Hoshino has starred in several dramas in recent years. Her main role in Platonic Sex was some-what controversial as it was rather contrary to her image as one possessing pure values. She has also published two photographic books as well as about six C.D.s. Of the Japanese dramas shown in Los Angeles, a substantial fraction of them has Mari in the cast.