Marcus Fysh was elected as a Member of Parliament for the Yeovil constituency on 7 May 2015. He was re-elected with an increased majority at the 2017 general election and then increased his majority further in 2019.
Before becoming a Minister, Fysh chaired the All-Party Parliamentary Group on Education. He has been a member of All-party parliamentary groups for the Armed Forces, for Housing, for Education, for Social Care, for County Councils, and for Women Against State Pension Inequality.
In the House of Commons, he sat on the European Scrutiny Committee, and has been a member of the International Trade Select Committee and the Public Administration and Public Affairs Committee.
In March 2019, Fysh was one of 21 MPs who voted against LGBT-inclusive sex and relationship education in English schools, citing concerns about the teaching of gender fluidity confusing very young children.
In June 2020, the Parliamentary Commissioner for Standards found that Fysh should have registered his unremunerated company directorships as interests. The Committee noted: “We do not believe that Mr. Fysh has acted in bad faith. He exercised his right as a Member of the House to express disagreement with the Commissioner’s interpretation of the rules and bring the matter before the Committee. It added that he should “make an apology on the floor of the House for both the non-registrations and non-declarations by means of a personal statement.” Fysh was also told to apologise to the commissioner and registrar in writing. Fysh then issued two apologies.
In October 2021, Fysh officially opened the construction site for upgrades to the A303, having campaigned on the issue for years.