Mraz or Mráz is a Slavic surname. It means "frost" and is cognate to Mroz and Moroz. It may refer to:
Franjo Mraz, Croatian artist
George Mraz, jazz bassist
Gustáv Mráz, Slovak footballer
Ivan Mráz, Czechoslovak footballer
Jason Mraz, American singer-songwriter
Ladislav Mráz, Czech opera singer
Patrik Mráz, Slovak footballer
Pavel Mráz, Czech canoer
Peter Mráz, Slovak footballer
Rani Mraz, Yugoslav rock band
Aircraft
Beneš-Mráz, airplane manufacturer
Mráz Sokol, manufactured by Benes
Mráz Skaut, manufactured by Benes