Trojanowski is a Polish masculine surname, its feminine counterpart is Trojanowska. Its Russian and Ukrainian versions ({{lang-ru|Трояновский}}, {{lang-uk|Трояновський}}) are transliterated as Troyanovsky, Troyanovski, Troyanovskyi (masculine) or Troyanovskaya (feminine). It may refer to:

• Daniel Trojanowski (born 1982), Polish rower
• Eduard Troyanovsky (born 1980), Russian boxer
• Izabela Trojanowska (born 1955), Polish singer and film actress
• John Q. Trojanowski (born 1946), American scientist
• Mieczyslaw Rys-Trojanowski (1881–1945), Polish general
• Oleg Troyanovsky (1919–2003), ambassador of the Soviet Union to Japan and China
• Tadeusz Trojanowski (1933–1997), Polish wrestler
• Wincenty Trojanowski (1859–1928), Polish painter
• Yevhen Troyanovskyi (born 1993), Ukrainian football player

• The Birthday Palace
• The Birthday Party (album)
• The Birthday Party (Birthday Party album)
• The Birthday Party (Motorhead video)
• The Birthday Party (novel)
• The Birthday Party (The Birthday Party album)
• The Birthday Present
• The Birthday Present (novel)
• The Birthday Problem
• The Birthday Show
• The Birthening
• The Birth (EP)
• The Birthgrave
• The Birthgrave Trilogy
• The Birthing of Hannibal Valdez
• The Birth of a Family
• The Birth Of Alternative Vol. 1
• The Birth of Alternative Vol. 1
• The Birth Of Alternative Vol. 2
• The Birth of Alternative Vol. 2
• The Birth Of A Nation
• The Birth Of A Prince
• The birth of a race
• The Birth of Coffee
• The Birth of Evil (album)