Malibu (/ˈmælɪbuː/ ^ⓘ MAL-ih-boo; Chumash: Humaliwo; Spanish: Malibú) is a beach city in the Santa Monica Mountains region of Los Angeles County, California, about 30 miles (48 km) west of Los Angeles. It is known for its Mediterranean climate, its strip of beaches stretching 21 miles (34 km) along the Pacific coast, and for its longtime status as the home of numerous Hollywood celebrities and executives with a high proportion of its residents in the entertainment industry. The Pacific Coast Highway (State Route 1) traverses the city, following along the South Coast of California. As of the 2020 census, the city's population was 10,654. The 2025 Palisades Fire devastated Malibu, with almost all of the beachfront homes near its center destroyed.

Nicknamed "The 'Bu" by surfers and locals, Malibu is noted for its beaches. The many parks within the Santa Monica Mountains National Recreation Area lie along the ridges above the city.

The city is bounded by the Santa Monica Mountains to the north, Topanga to the east, Solromar to the west, and the ocean to the south. The Malibu ZIP Code includes residents of the unincorporated canyon areas as it was assigned before the city incorporated.

The area is within the Ventureño Chumash territory, which extended from the San Joaquin Valley to San Luis Obispo to Malibu, as well as several islands off the southern coast of California. The Chumash called the settlement Humaliwo or "the surf sounds loudly". The city's name derives from this, as the "Hu" syllable is not stressed.

Humaliwo was an important regional center in prehistoric times. The village, which is identified as CA-LAN-264, was occupied from approximately 2500 BCE. It was the second-largest Chumash coastal settlement by the Santa Monica Mountains, after Muwu (Point Mugu). This pre-colonial village was next to Malibu Lagoon and is now part of the State Park.

Humaliwo was considered an important political center, but there were additional minor settlements in the area. One village, Ta'lopop, was a few miles up Malibu Canyon from Malibu Lagoon. Research shows that Humaliwo had ties to other pre-colonial villages, including Hipuk (in Westlake Village), Lalimanux (by Conejo Grade) and Huwam (in Bell Canyon).

Conquistador Juan Rodríguez Cabrillo is believed to have moored at Malibu Lagoon, at the mouth of Malibu Creek, to obtain fresh water in 1542. The Spanish presence returned with the California mission system, and the area was part of Rancho Topanga Malibu Sequit—a 13,000-acre (53 km²) land grant—in 1802. Baptismal records list 118 individuals from Humaliwo. That ranch passed intact to Frederick Hastings Rindge in 1891. He and his wife, Rhoda May Knight Rindge, staunchly protected their land. After his death, May guarded their property zealously by hiring guards to evict all trespassers and fighting a lengthy court battle to prevent the building of a Southern Pacific railroad line through the ranch. Interstate Commerce Commission regulations would not support a railroad condemning property in order to build tracks that paralleled an existing line, so Frederick Rindge built his own railroad through his property first. He died, and May followed through with the plans, building the Hueneme, Malibu and Port Los Angeles Railway. The line started at Carbon Canyon, just inside the ranch's property eastern boundary, and ran 15 miles westward, past Pt. Dume.

Few roads even entered the area before 1929, when the state won another court case and built what is now known as the Pacific Coast Highway. By then May Rindge was forced to divide her property and begin selling and leasing lots. The Rindge house, known as the Adamson House (a National Register of Historic Places site and California Historical Landmark), is now part of Malibu Creek State Park, between Malibu Lagoon State Beach and Surfrider Beach, beside the Malibu Pier that was used to provide transportation to/from the ranch, including construction materials for the Rindge railroad, and to tie up the family's yacht.