Ubolratana Narinaga, Princess Argavoraraja Kalya[1] (Thai: อุบลรัตนนารีนาค, RTGS: Ubonrat Narinak, Uppalaratananārīnāga), born Princess Bua Ladavalya (Thai: บัว ลดาวัลย์; RTGS: Bua Ladawan; 28 November 1846 – 15 October 1901) was a consort of Chulalongkorn, the King of Siam.
She was a daughter of Ladavalya, Prince Bhumindra Bhakdi and Lady Chin.