| Prabha Bannabilaya | |
| Full Name: | Prabha Bannabilaya |
| House: | Chakri Dynasty |
| Mother: | Chao Chom Manda Phrom |
| Birth Date: | 13 August 1885 |
| Birth Place: | Grand Palace Bangkok, Siam |
| Death Place: | Bangkok, Thailand |
Princess Prabha Bannabilaya (Thai: ประภาพรรณพิไลย; ; 13 August 1885 - 8 September 1948) was the Princess of Siam (later Thailand. She was a member of Siamese Royal Family. She is a daughter of Chulalongkorn, King Rama V of Siam.
Her mother was Chao Chom Manda Phrom (daughter of Phraya Phitsanuloka Thibodi). She had 3 siblings; 1 elder sister, 1 younger brother and 1 younger sister;
Princess Prabha Bannabilaya and Princess Prabai Bannabilas were the only twin couple of King Chulalongkorn, and they were the 4th twin couple in Chakri Dynasty. The three previous twin couple were:
Princess Prabha Bannabilaya died on 8 September 1948, at the age of 63. The Royal Cremation was created on 23 April 1950, in the same crematorium of King Ananda Mahidol's crematorium. The Royal Cremation was performed by King Bhumibol Adulyadej
| Princess Prabha Bannabilaya | Father: Chulalongkorn, King Rama V of Siam | Paternal Grandfather: Mongkut, King Rama IV of Siam | Paternal Great-grandfather: Buddha Loetla Nabhalai, King Rama II of Siam |
| Paternal Great-grandmother: Queen Sri Suriyendra | |||
| Paternal Grandmother: Queen Debsirindra | Paternal Great-grandfather: Prince Sirivongse, the Prince Matayabidaksa | ||
| Paternal Great-grandmother: Mom Noi Sirivongs na Ayudhya | |||
| Mother: Chao Chom Manda Phrom | Maternal Grandfather: Phraya Phitsanuloka Thibodi | Maternal Great-grandfather: unknown | |
| Maternal Great-grandmother: unknown | |||
| Maternal Grandmother: unknown | Maternal Great-grandfother: unknown | ||
| Maternal Great-grandmother: unknown |