Sim Kui Hian (born 18 August 1965) is a Malaysian politician and cardiologist who served as Deputy Premier of Sarawak since 2022. A president of Sarawak United Peoples' Party, he represented Batu Kawah in Sarawak State Legislative Assembly since 2016. He also served as Minister of Public Health, Housing and Local Government Sarawak since 2022.

Born in Sarawak, Sim graduated from Monash University. Sim is Sarawak's first deputy premier of Chinese descent in more than a decade after George Chan Hong Nam stepped down in 2011. Previously, he served as the Minister of Local Government Sarawak from May 2016 to January 2017 under Adenan Satem's cabinet, and Minister of Local Government and Housing Sarawak from January 2017 to December 2021 under Abang Johari's first cabinet. He also had served as Senator in the Parliament of Malaysia from April 2014 to April 2017.

Additionally, he holds a watching brief role which gives him oversight over the Sarawak Health Department and the Sarawak Fire and Rescue Department, both agencies of the Malaysian federal government. He is also one of the founding Vice Chairmen of the GPS coalition, in which SUPP is a co-founding component party.

While acknowledging that the region of Sarawak is part of Malaysia, Sim is one of the most vocal and consistent proponents for more Sarawakian autonomous power and rights, based on the unique contexts of the Malaysia's formation as originally outlined in the Malaysia Agreement 1963 (MA63), Inter-Governmental Committee (IGC) Report and recommendations, and the Report of the Cobbold Commission.

Sim has taken part in major policy decisions through the years. He was first to announce about the Sarawak Cabinet and then- Chief Minister Adenan Satem's decision to officially recognise the Unified Examination Certificate (UEC) of Chinese independent schools, embracing graduates of the system into joining the Sarawak-owned universities, scholarships and even the Sarawak Civil Service (with national language qualifications). He also formed Sarawak Medical Committee (SMC) under the umbrella of the Malaysian Medical Council (MMC), while frequently invoking Sarawak's historical medical board framework to justify Sarawak Health Autonomy.

Sim has tabled a host of bills passed in the Sarawak Legislative Assembly. Among others, include The Building (Amendment) Bill 2025, which includes the Sarawak Building Board (SBB), accredited checkers for structural design reviews, professional oversight for architects and engineers and qualified persons, and mandatory green building standards; and The Strata Management Bill 2019, which outlines provisions of mandatory maintainence; developer liability on unsold units; and mandate elected management committees for stratified buildings.

Sim is the son of father Tan Sri Datuk Amar Sim Kheng Hong (Chinese: 沈庆鸿) who was the Deputy Chief Minister of Sarawak from 1974 to 1991; and mother Puan Sri Datin Amar Lim Su Kheng (Chinese: 林素卿). He received his primary education at Chung Hua Primary School No.4 and his secondary education in St. Joseph's Secondary School, Kuching. After that, he completed his Higher School Certificate at St. Bede's College in Mentone, in Victoria, Australia. He graduated with an MBBS from Monash University's Alfred Medical School and completed his cardiology fellowship at Monash Medical Centre in Melbourne.

When Sim found out that the Sarawak General Hospital (SGH) was attempting to set up a cardiology unit, he left his practice and returned to Malaysia in 1998, after spending 17 years in Australia. In 2001, the Cardiology Department of SGH was set up. The department had progressively evolved into a cardiology centre (SGH Heart Centre, which later renamed Sarawak Heart Centre) with its own standalone facilities in Kota Samarahan and a recognised training centre for cardiothoracic surgeons.