The 18th South African Parliament was the eighteenth Parliament of South Africa to convene since the unification of South Africa in 1910 and the sixth to convene since the adoption of the republican constitution in 1961. It was elected in the 1981 South African general election and consisted of the unicameral House of Assembly. The House of Assembly contained 165 members.

Three parties were represented in this parliament: the National Party (NP), the Progressive Federal Party (PFP), and the New Republic Party (NRP). The National Party retained a diminished majority: it won 131 of the 165 seats, a decrease from the 134 seats it held in the 17th Parliament.

Summary by province

The table below gives the number of registered voters (all of whom were classified as white under the apartheid legislation) and parliamentary seats, on the day of the election, broken down by province.^[1] The provinces are those which existed prior to 1994.

Parties represented

Members of Parliament

The following is a list of MPs elected in the 1981 general election to the 18th Parliament, which sat until the 1987 general election.^[2]