Biñan (Tagalog pronunciation: [biˈɲan]), officially the City of Biñan (Filipino: Lungsod ng Biñan), is a component city in the province of Laguna, Philippines. According to the 2024 census, it has a population of 584,479, making it the most populous city in the province of Laguna.

Biñan has become both a suburban residential community of Metro Manila and a location for some of the Philippines' largest industrial estates and export processing zones. Prior to its cityhood in 2010, Biñan was the richest municipality in the Philippines with an annual gross income of ₱677 million (US$14.383 million) and net income of ₱250 million (US$5.308 million), as of 2007 by the Commission on Audit.

Where Biñan got its name is a mystery. Some deduced that before Captain Juan de Salcedo proceeded to Cainta and Taytay finally reaching Bay, he landed in Biñan. According to the story, Catholic priests Alfonso de Alvarado and Diego Espinar planted a huge wooden cross on the spot where the present-day San Isidro Labrador Parish stands and co-celebrated a Thanksgiving Mass. Curious natives gathered and the two Spanish missionaries took advantage of the situation. They baptized each one of them. From then on, old folks say they called the place “Binyagan,” which means a baptismal place in Tagalog. The place's root word binyag is originally a Brunei Malay word which means “to pour water from above,” according to the dictionary Vocabulario de la lengua tagala. The Spanish tongue's difficulty in pronouncing the local dialect acquired for the once town its name — "Biñan".

An 1846 book in French also spelled the town as Viñan. It is also spelled in other references as Biniang, Binyang, Binang, or Biñang.

Captain Juan de Salcedo explored Laguna de Bay and founded Biñan at the end of June 1571, a month after Miguel López de Legazpi established Manila. In 1644, Dominican friars turned the area into a hacienda known as Hacienda de San Isidro Labrador de Biñán, in honor of Saint Isidore the Laborer. When the seat of the provincial government of the Provincia de la Laguna de Bay was transferred from Bay to Pagsanjan in 1688, Biñan separated from Tabuco (now the city of Cabuyao). In the 1600s Biñan had 256 Chinese-Filipino and 1,639 Native Filipino tributes.

In 1747, the Spaniards officially converted Biñan into a pueblo (town). Santa Rosa separated from Biñan in 1791 and was later established as an independent town on January 18, 1792.

Historically, Biñan has gained recognition nationwide for being part of the life of José Rizal, one of the country's national hero. In June 1869, when Rizal was a child, he traveled to Biñan with his brother Paciano. They moved into his aunt's home, which would serve as their lodging, near the town proper. Here, he received his first formal education through the tutelage of Maestro Justiniano Aquino Cruz and, after a year and a half of instruction, recommended the young Rizal to pursue higher education in Manila. The home where José Rizal resided was given a plaque of appreciation in his honor. Biñan's town square now has a monument in the center honoring Biñan's connection to Rizal.

In 1903, the adjacent towns of Muntinlupa, then part of Rizal province, and San Pedro Tunasan were consolidated with Biñan. Both towns were later separated when Muntinlupa was returned to Rizal as part of Taguig in 1905 and San Pedro Tunasan regained its independent municipality status effective 1907.