Santo Niño, officially the Municipality of Santo Niño (; ; ), is a municipality in the province of Samar, Philippines. According to the 2024 census, it has a population of 13,088 people.
Formerly known as Limbancauayan, it consists of the northern island of Camandag and the larger Santo Niño Island about to the south. In between those two islands is the smaller Pilar Island. The municipality's poblacion (town center) is located in Santo Niño Island.
This town has an ancient Bisayan name Limbankawayan which derived from the word limba meaning red and kawayan means bamboo thus a red colored bamboo (phyllostachys iridescens) which is abundant during those days.
It was separated from Calbayog and made a pueblo and a parish by a Royal Decree of September 29, 1898. The Bishop of Cebu had recommended in 1895 that it achieve parish status, though final approval and confirmation was not relayed from Madrid through Manila until the year 1897.
Santo Niño consists of three islands: Santo Niño Island, Camandag Island and Pilar Island. These islands are located in the Samar Sea about south-west of Calbayog on the main island of Samar.
The larger Santo Niño Island is about north-west of Maripipi, Biliran province with an area of about . Both islands are volcanic in origin with Santo Niño having the highest elevation in the municipality at .
The circular Camandag Island is located north of Santo Niño Island, about shore to shore. It has area of about with an elevation of .
The smallest island of the municipality is located off north-west of Santo Niño Island and about south-west of Camandag Island. Pilar Island has an elevation of .
Santo Niño is politically subdivided into 13 barangays. Each barangay consists of puroks and some have sitios.
There are no airports on the islands of Santo Niño and Camandag. The islands are reached by boats from the Port of Calbayog.