Herbert J. Krapp (1887, in New York City, New York – 1973, in Florida) was a theatre architect and designer in the early part of the twentieth century.

Krapp was an apprentice with the Herts & Tallant firm until 1915. Between 1912 and 1916 Krapp began working directly with the Shubert brothers and eventually would become their primary architect. He also designed theatres for the Chanin brothers. Almost half of the current Broadway theatres were designed by Krapp, including the Lyceum, Shubert, Booth, New Amsterdam and Longacre Theatres.

Krapp was well known for his ability to use his building space to its fullest potential. For the Majestic Theatre, Krapp incorporated stadium seating into the plans for the orchestra level, creating better sightlines and allowing for the creation of larger lounge and lobby areas. He designed the Ambassador Theatre on a diagonal plan to fit it into a small site. Krapp renovated the Winter Garden Theatre and the Helen Hayes Theatre in the 1920s. He also designed the Hotel Edison, the Lincoln Hotel (now the Row NYC Hotel), and numerous other buildings.

Although the stock market crash of 1929 brought an end to the theatre building boom, Krapp remained with the Shuberts until 1963, supervising the maintenance and renovations of the existing venues. He also experimented with inventing; one of the tools he created was patented and used by the U.S. Air Force. He died in Florida in 1973.