Wilshire Boulevard (/ˈwɪlʃər/ WIL-shər) is a prominent 15.83 mi (25.48 km) boulevard in the Los Angeles area of Southern California, extending from Ocean Avenue in the city of Santa Monica east to Grand Avenue in the Financial District of downtown Los Angeles. One of the principal east–west arterial roads of Los Angeles, it is also one of the major city streets through the city of Beverly Hills. Wilshire Boulevard runs roughly parallel to Santa Monica Boulevard from Santa Monica to the west boundary of Beverly Hills. From the east boundary, it runs a block south of Sixth Street to its terminus.

Wilshire Boulevard is densely developed throughout most of its span, connecting five of Los Angeles's major business districts and Beverly Hills. Many of the post-1956 skyscrapers in Los Angeles are located along Wilshire; for example, the Wilshire Grand Center, the tallest building in California, sits at the intersection of Figueroa Street. One Wilshire, built in 1966 at the junction of Wilshire and Grand, is said to be "the main hub of the internet for the entire Pacific Rim" because so many telecommunications companies rent space there. Aon Center, Los Angeles' third-largest tower, is at 707 Wilshire Boulevard in downtown Los Angeles.

The stretch of the boulevard between Fairfax and Highland Avenues, known as the Miracle Mile, is home to many of Los Angeles's largest museums and cultural institutions. The area just to the east, between Highland Avenue and Wilton Place, is referred to as the Park Mile. Between Westwood and Holmby Hills, several tall glitzy condominium buildings overlook this part of Wilshire, which is variously referred to as Millionaire's Mile, the Wilshire Corridor, and Condo Canyon.

The Wilshire Corridor, located next to Century City, is one of Los Angeles's busiest districts, and contains many high-rise residential towers. The Fox and MGM studios are located in a series of skyscrapers, along with many historic Los Angeles hotels.

Wilshire Boulevard is also the principal street of Koreatown, the site of many of Los Angeles' oldest buildings and skyscrapers. Koreatown and Mid-Wilshire are among Los Angeles's most densely populated districts.

Wilshire Boulevard originated as one of the central pathways constructed by the Tongva tribes residing in the region prior to the exploration of the conquistadores. At the time of the founding of Los Angeles, Wilshire Boulevard was one of the main arteries connecting the largest Tongva village in the area, then known as Yaanga, which eventually became Union Station, to the Pacific Ocean.

From the founding of Los Angeles through nearly all of the 1800s, Wilshire Boulevard was known as "Calle de los Indios."

Before the Spanish settlements of Los Angeles, much of the length of Wilshire Boulevard can be traced back to the indigenous Tongva people who used it to bring back tar from the La Brea pits in today's Miracle Mile section of Wilshire Blvd, back to their settlement on the coast. This road was later used by Spanish explorers and settlers, calling it El Camino Viejo ('The Old Road'). The route that ultimately became Wilshire crossed the original pueblo of Los Angeles and five of the original Spanish land grants, or ranchos.