Sahibzada Mīrzā Mu'hammad Jalāl ud-Dīn Mridha Sahib (Urdu: جلال الدینہ محمد میرزا‎), better known as Jalaluddin Mirza (1898-1975), was a Bengali Indian aristocrat in the erstwhile British Empire who served as the fifth and last hereditary Zamindar of Natore from the House of Singra and Natore before it was abolished in 1951.

He was born in 1898 as the son of Sahibzada Muhammad Mirza Jafaar (1876-1921) and his principle first wife, in Mirza Mahal palace in Natore and educated at the Rajshahi Collegiate School alongside the Dighapatia princes. He was named by his grandfather Sahibzada Zahir Shah Mirza (1855-1899) after his illustrious ancestor Mirza Jalaluddin Muhammad (1542-1605). He married Jamila Begum, the first in a long line to practice monogamy.

His father served as the "Mridha" or the Military Governor to the Maharaja of Rajshahi, while he paid tributary to the Maharaja of Dighapatia as a Madhyasvatva (subinfeudated or vassal) as after his father death he took over the dignitaries as the zamindar. One of the few Muslim zamindari in Natore, during the Partition of India in 1947 the newly formed Islamic Government of Pakistan favored Muslim families and especially when Bengal was split the old Hindu Rajas (Kings) of East Bengal left resulting in most of the neighboring estates coming under him and his full brothers. From his fathers death in 1921 till his election as the Zamindar in 1932, his brothers managed the Singranatore estate.