The Kew Ong Yah Temple (Upper Serangoon) is the oldest temple in Singapore that is dedicated to the worship of the 9 Emperor Gods (九皇爷 or Jiuhuang Ye). Throughout its history, the temple has been popularly known as Kew Ong Yah temple among the Hokkien and Teochew communities. According to anecdotal accounts and temple inscriptions, the founders of Hougang Tao Mu Temple invited the incense of the 9 Emperor Gods from Tow Boe Keong Kew Ong Tai Tay Temple （槟城香港巷九皇大帝庙） in Penang – an old temple that was established in 1842. During the mid-19th century, tin-mining industry bloomed in Southeast Asia. Many Chinese who lived in the coastal regions in Southeast China left for Penang to make a living.

A majority of them were from Fujian province. According to Khoo Poh Ong, the fourth generation caretaker of Tow Boe Keong, the incense of the 9 Emperor Gods was brought to Penang by a Fujian captain and his crew on their voyage to Penang. Back then, medical conditions were poor, and epidemics were common. It was said that practicing Jiuhuang retreat (九皇斋) could help eliminate disasters and relief diseases. Naturally, people started to pray to the Nine Emperor Gods for protection. As time passed, the worship of the 9 Emperor Gods took rooted and spread far and wide.