Faj may refer to:

• Fáj, a village in Hungary
• Faj, Iran, a village in Chaharmahal Province, Iran
• Air Fiji, a defunct Fijian airline
• Diego Jiménez Torres Airport, in Puerto Rico, United States
• Faita language, spoken in Papua New Guinea

• Ludwig Rudolf, Duke of Brunswick-Wolfenbüttel
• Ludwig Rödl
• Ludwigsau
• Ludwigsburg district
• Ludwig's bustard
• Ludwig's Bustard (E)
• Ludwig Schmidseder
• Ludwig Schnorr von Carolsfeld
• Ludwigschorgast
• Ludwig Schuberth
• Ludwig Schupmann
• Ludwig Schwamb
• Ludwigsdorf
• Ludwig's double-collared sunbird
• Ludwig Sennfl
• Ludwigsfelde
• Ludwigsfelder FC
• Ludwigshöhe
• Ludwig Siebert (bobsleigh)
• Ludwig's Law
• Ludwigslied
• Ludwigslust district
• Ludwigslust, Germany
• Ludwigslust-Land
• Ludwigslust Palace