MV Doña Paz was a Japanese-built and Philippine-registered passenger ferry that sank after it collided with the oil tanker Vector on December 20, 1987.

Built by Onomichi Zosen of Hiroshima, Japan, the ship was launched on April 25, 1963 as the Himeyuri Maru with a passenger capacity of 608.

However, official blame was directed at the tanker Vector, which collided with the Doña Paz and was found to be unseaworthy and to be operating without a license, a lookout, or a qualified master.

[6][7] On December 20, 1987, at 06:30, Philippine Standard Time, Doña Paz departed from Tacloban, Leyte, for Manila,[6][8] with a stopover at Catbalogan, Samar.

[9] While most of the passengers slept, Doña Paz collided with MT Vector, a Philippine-owned oil tanker en route from Bataan to Masbate.

Vector was carrying 1.05 million L (8,800 US bbl) or 1,041 tonnes (1,148 short tons) of gasoline and other petroleum products owned by Caltex Philippines.

[12] According to the initial investigation performed by the Philippine Coast Guard, only one apprentice member of the crew of Doña Paz was monitoring the ship's bridge when the accident occurred.

[20] A similar testimony was given by one of the survivors, Luthgardo Niedo, wherein he stated that a fellow constabulary soldier informed him of "an ongoing party with laughter and loud music" on the ship's bridge with the captain as one of the attendees.

[23] CLSO was officially recognized by the Philippine government to be able to provide assistance to the MV Doña Paz's victims' relatives.

[8] A revised manifest released on December 23, 1987, showed 1,583 passengers and 58 crew members on Doña Paz, with 675 persons boarding the ferry in Tacloban, and 908 coming aboard in Catbalogan.

[14] However, an anonymous official of Sulpicio Lines told UPI that, since it was the Christmas season, tickets were usually purchased illegally aboard the ship at a cheaper rate, and those passengers were not listed on the manifest.

[26] On December 28, 1987, Representative Raul Daza of Northern Samar claimed that at least 2,000 passengers aboard Doña Paz were not on the ship's manifest.

[28] During February 1988 the Philippine National Bureau of Investigation stated, on the basis of interviews with relatives, that there were at least 3,099 passengers and 59 crew aboard, giving 3,134 on-board fatalities.

[29] During January 1999 a presidential task force report estimated, on the basis of court records and more than 4,100 settlement claims, that there were 4,342 passengers.

[32] Given the estimated death toll, Time magazine and others have termed the sinking of Doña Paz "the deadliest peacetime maritime disaster of the 20th century".

[34] Days later, hundreds of the victims' kin staged a mass rally at Rizal Park, demanding that the ship owners likewise indemnify the families of those not listed on the manifest, as well as to give a full accounting of the missing.

Located at adjacent to St. Bartholomew Church and Saint Mary's College of Catbalogan, the park now serves as a public space for families and friends of the victims.

[44] The wreck of Doña Paz was located in April 2019 by the RV Petrel, with video footage later released on December 19.