Khalil-ur-Rehman Ramday (Urdu: خلیل الرحمان رمدے) was an ad-hoc judge later appointed as a permanent judge of the Supreme Court of Pakistan. He remained permanent judge of Supreme Court from 2002 to 2010. He was born in Lahore on 13 January 1945. His late brother Chaudhary Muhammad Farooq had served as the Attorney General of Pakistan. His younger brother Chaudhary Asad-ur-Rehman, a politician, was elected as a Member of the National Assembly three times on a PML-N ticket and served as a Federal minister as well.
After receiving his early education in different schools of the Punjab, he matriculated from Central Model School, Lahore, and joined Government College, Lahore from where he migrated to Gordon College, Rawalpindi, on account of his father’s posting in the Federal Ministry of Law.
At Gordon College, Rawalpindi, he was the captain of the college tennis team. He was judged the best English and Urdu debater of the college. He also became the editor of the college magazine, "The Gordonian" and was later elected, un-opposed, as the president of the college Minerva Club.
After graduation, he joined the Punjab University Law College at Lahore, where he became secretary of the Punjab University Law Society, and the editor of the college magazine, "Al-Mizan". He was declared the best English debater of 1968 in the Punjab University after winning the "Krishan Kishore Grover Goodwill Gold Medal Declamation Contest". He graduated in 1968 with a top honours for best all round activities in academics, sports and debates. 
Khalil ur Rehman Ramday himself was appointed Advocate General of Punjab in 1987 when PML-N leader Mian Nawaz Sharif was Chief Minister of the province. Before that he was servign as Depurty Advocate General of province since 1984. He was among a large number of judges who were appointed in different high courts just before 1988 elections in anticipation of PPP's victory. The move was seen to be aimed at denying PPP government right to nominate judges in the courts.
Khalil-ur-Rehman Ramday was married to the daughter of former chief justice of Pakistan Justice Yaqoob Ali Khan, Quratulain Ramday (late). Mrs. Ramday was the chairperson of the Asia Chapter of Asia Pacific Cultural Center for UNESCO (ACCU) and the Punjab chapter of All Pakistan Women Association (APWA). She was also a Member of the Board of Governors of Queen Mary College Lahore. Mrs. Ramday died on Saturday, 9 January 2010, and was survived by her son, Mustafa and daughter, Aamena.
Justice Ramday joined the legal profession at Lahore and enrolled as an advocate of the subordinate Courts in 1969. In 1971, he became an advocate of the High Court and in 1976 as an advocate of the Supreme Court.
In April 1976, he was appointed Assistant Advocate General of the Punjab, was promoted to Additional Advocate General in 1984, and was finally appointed as the Advocate General in March 1987.
In October 1988, Justice Ramday was elevated to the bench of the Lahore High Court and was promoted to the judge of the Supreme Court of Pakistan in January 2002. He became famous for presiding over the bench in the Chief Justice of Pakistan Iftikhar Muhammad Chaudhry versus the Government of Pakistan in 2007.
On 3 November 2007, Chief of the Army declared emergency and issued a Provisional Constitutional Order (PCO). A seven panel Supreme Court bench headed by Chief Justice Iftikhar Muhammad Chaudhry declared emergency as illegal and passed order that no judge of any superior court shall take oath on PCO. Justice Ramday refused to take oath on PCO as per ruling of Supreme Court. He was declared to be not holding office of the Justice any more. During the unrest that followed the imposition of emergency, he was placed under house arrest, along with many other judges of the Supreme and High Courts who had refused to take oath under the Provisional Constitutional Order.
Justice Ramday was restored to the bench of Supreme Court on 17 March 2009 as a result of historic movement that lasted for two years.