Albert Cornelis "Appie" Baantjer (1923–2010) was a Dutch author of detective fiction and police officer. He is mainly known for his series of detective novels revolving around police inspector De Cock and his side-kick, sergeant Vledder. The novels have spin-offs in the form of a motion picture and a long-running TV-series entitled 'Baantjer' - named after the author, rather than the main character(s).

Baantjer's novels have made their way into the English language through publishing house Speck Press. De Cock's name has been translated as DeKok. Approximately 23 of the 60 published Baantjer titles are available in English. His books have also been translated into Spanish, French, Russian and Korean and Estonian.