Blue star or bluestar may refer to:

• O-type star (a.k.a. blue star), a stellar classification

Animals

• Linckia laevigata, a sea star from the Indian and West Pacific Oceans
• Phataria unifascialis, a sea star from the East Pacific

Businesses

• Blue Star (company), an Indian Air conditioning company
• Blue Star Ferries, a Greek ferry company
• Blue Star Infotech, Indian company
• Blue Star Line, a former British shipping company
• Blue Star Productions, a publishing imprint and a division of Book World, Inc
• Bluestar (bus company), based in Southampton, England
• Bluestar Company, a predecessor of ChemChina

Military

• Operation Blue Star, a 1984 Indian military operation
• Blue stars used on service flags denote a United States service member fighting in a war
  • Blue Star Memorial Highway, a system of highway markers honoring veterans
  • Blue Star Mothers Club, a non-profit military support group

Music

• "Blue Star" (song), first recorded 1955
• Blue Star (album), is an album by Levinhurst

Plants

• Amsonia, plant species also named "bluestar"
  • Hubricht's Bluestar (Amsonia hubrichtii), plant
• Isotoma axillaris

Others

• The Blue Star (novel), a 1952 fantasy novel by Fletcher Pratt
• The Blue Star (film), a 2023 Spanish-Argentine drama film
• Newcastle Blue Star F.C., English association football team
• Blue star, the logo of Newcastle Brown Ale
• BlueStar PR, Jewish political organization
• Tesla BlueStar, code name for the Tesla Model 3 electric car
• Blue Star Wicca, a sect of traditionalist witches
• Blue Star, a nickname for the United States business band frequency of 467.925 MHz
• Blue Star (SLV), satellite launcher
• Blue star tattoo legend
• Blue Star, a type of Multiple working system used on British locomotives
• Blue Star Kachina, a legendary spirit

See also

• Blue Stars (disambiguation)
• Blue (disambiguation)
• Star (disambiguation)
• Blue giant (disambiguation)
• Blue dwarf (disambiguation)
• Blue Planet (disambiguation)
• Blue world (disambiguation)