Discman was the product name given to Sony's first portable CD player, the D-50, which was the first on the market in 1984, and adopted for Sony's entire portable CD player line. In Japan, all Discman products are referred to as "CD Walkman" and the name was adopted worldwide in 2000 along with a redesigned "Walkman" logo.

Prior to the development of the CD, cassette tapes were the dominant form of audio storage in regards to the then-fledgling portable audio industry. In 1979, Sony had revolutionized the way in which music could be enjoyed with the introduction of the first portable music player, the Walkman. With this portable unit, music was able to accompany a person anywhere it went. Gone were the restrictions of a stationary player. The Walkman became part of culture and even part of fashion. As Sony began to realize the potential of the CD, executives pushed for a means to give the CD player market momentum, moving it from audio enthusiasts to the mainstream.

Building on the design of the CDP-101, a CD player, Sony worked towards both improving the design of the player, reducing the power and number of parts needed while decreasing the overall size of the player, as well as reducing the cost of the player to a 50 000 - 60 000 yen range in what was called the "CD CD Project", which stood for Compact Disc Cost Down Project. With the ability to produce a CD player one-tenth the size of its first unit by August 1983, there became potential for a portable player.