Ben Cooper, Inc. was a privately held American corporation founded in 1937 which primarily manufactured Halloween costumes from the late 1930s to the late 1980s. It was one of the three largest Halloween costume manufacturers in the U.S. from the 1950s through the mid-1980s. The company's inexpensive plastic masks and vinyl smocks were an iconic American symbol of Halloween from the 1950s to the 1970s, for which Cooper has been called the "Halston of Halloween" and the "High Priest" of Halloween.

Founder Ben Cooper was born on the Lower East Side of New York City in 1906. He studied accounting and briefly sought a career as a songwriter before founding a theatrical costume business in 1927. Cooper designed costumes and sets for the legendary Cotton Club in Harlem and several editions of the Ziegfeld Follies.

With live theatre becoming rarer in the 1930s due to the Great Depression and Halloween becoming a more popular holiday, Cooper established Ben Cooper, Inc., in Brooklyn, New York, in 1937. The firm assumed control of A.S. Fishbach, Inc.—which had a license to produce costumes based on characters owned by The Walt Disney Company such as Donald Duck and Snow White—in 1937 and began selling Disney costumes under Fishbach's Spotlight brand. The two companies formally merged and incorporated as Ben Cooper, Inc., on December 8, 1942.

By the late 1940s, Ben Cooper, Inc. was one of the largest and most prominent Halloween costume manufacturers in the United States. Its costumes were generally very thin fabric with a silk-screened image on the front that sold for less than $3. The company began selling its costumes through large retailers such as J. C. Penney, Sears, Woolworth's, and five-and-dime stores. Costumes often sold for $1.25 ($18 in 2025 dollars). At the time, the most popular costumes were traditional Halloween figures such as devils, ghosts, skeletons, and witches. In the 1950s, television characters such as Davy Crockett, Superman, and Zorro were more popular. As parents became more concerned about safety in the 1950s, the company responded by creating its "Glitter Glo" costumes, dresses, and jumpsuits with large amounts of blue glitter glued to the front (which would reflect the headlights of oncoming automobiles). The company banked heavily on the popularity of President John F. Kennedy and Jacqueline Kennedy, but had to destroy thousands of masks after Kennedy was assassinated in November 1963.

In the 1960s and 1970s, Ben Cooper, Inc., was one of the "big three" Halloween costume companies, along with Collegeville and the H. Halpern Company (Halco). The company became known for licensing popular film and television characters and getting their images onto store shelves quickly. For example, it licensed Spider-Man, a virtually unknown character at the time, in 1963. The company also licensed the Batman character in 1964. The company was the first to license anything depicting Marvel superheroes.

The company produced a very popular Richard Nixon mask in the late 1960s, which sold as equally well as its Ronald Reagan mask even in the late 1980s. The company produced a George H. W. Bush mask in 1987, anticipating Bush's election as president by a year. In 1979, Ben Cooper, Inc., was still the largest Halloween costume company in the U.S. That same year, the firm issued its first costume based on a character in an R-rated motion picture, the creature from the film Alien.

The company suffered heavy financial losses in the early and mid-1980s. Beginning on September 29, 1982, seven people died after taking the painkiller Tylenol. Investigators discovered that someone had tampered with the product, lacing it with potassium cyanide. Terrified parents nationwide refused to allow their children to celebrate Halloween the following month, and sales of costumes plummeted and did not recover for several years. Ben Cooper, Inc. formed the Halloween Celebration Committee along with eight other manufacturers of Halloween costumes, masks, makeup, and accessories and (in cooperation with the Toy Manufacturers of America) published the booklet "13 Great Ways to Celebrate Halloween" in order to reassure parents and help stimulate interest in the holiday again. Despite this setback, in 1984 the firm was still the largest supplier of Halloween costumes in the United States. The company recovered around 1987, as total sales of accessories, costumes, and makeup rose at an annual rate of 20 percent a year.

A 2024 documentary by Rob Caprilozzi, Dressing Up Halloween: The Story of Ben Cooper, Inc. traces the firm's corporate history. In it, the son of costume designer Frank Romano, states that the reason that the costumes had an image of the character on the front was that children often moved the sweat-inducing masks off their faces and wore them atop their heads and the licensing agreements required that the characters always be recognizable.