The 1978 United States House of Representatives elections in South Carolina were held on November 7, 1978, to select six Representatives for two-year terms from the state of South Carolina. The primary elections for the Democrats and the Republicans were held on June 13. All five incumbents who ran were re-elected, but the open seat in the 4th congressional district was taken by the Republicans from the Democrats. The composition of the state delegation after the elections was four Democrats and two Republicans.
Incumbent Democratic Congressman Mendel Jackson Davis of the 1st congressional district, in office since 1971, defeated Benjamin Frasier in the Democratic primary and Republican C.C. Wannamaker in the general election.
| Democratic primary | ||
|---|---|---|
| Candidate | Votes | % |
| 48,541 | 86.4 | |
| Benjamin Frasier | 7,631 | 13.6 |
|-| | colspan=5 |Democratic hold|-
Incumbent Republican Congressman Floyd Spence of the 2nd congressional district, in office since 1971, defeated Democratic challenger Jack Bass.
| Democratic primary | ||
|---|---|---|
| Candidate | Votes | % |
| Jack Bass | 34,630 | 57.6 |
| B.E. Hadley | 25,520 | 42.4 |
|-| | colspan=5 |Republican hold|-
Incumbent Democratic Congressman Butler Derrick of the 3rd congressional district, in office since 1975, defeated Republican challenger Anthony J. Panuccio.
|-| | colspan=5 |Democratic hold|-
Incumbent Democratic Congressman James R. Mann of the 4th congressional district, in office since 1969, opted to retire. Carroll A. Campbell Jr., a Republican state senator from Greenville, defeated Robert Watkins in the Republican primary and Democrat Max M. Heller in the general election.
| Democratic primary | ||
|---|---|---|
| Candidate | Votes | % |
| Max M. Heller | 25,295 | 53.1 |
| 22,319 | 46.9 | |
| Republican primary | ||
|---|---|---|
| Candidate | Votes | % |
| 6,808 | 88.3 | |
| Robert Watkins | 899 | 11.7 |
|-| | colspan=5 |Republican gain from Democratic|-
Incumbent Democratic Congressman Kenneth Lamar Holland of the 5th congressional district, in office since 1975, defeated Colleen H. Yates in the Democratic primary and Independent Harold Hough in the general election.
| Democratic primary | ||
|---|---|---|
| Candidate | Votes | % |
| 46,247 | 65.0 | |
| Colleen H. Yates | 24,853 | 35.0 |
|-| | colspan=5 |Democratic hold|-
Incumbent Democratic Congressman John Jenrette of the 6th congressional district, in office since 1975, defeated Jeryl Best in the Democratic primary and was unopposed in the general election.
| Democratic primary | ||
|---|---|---|
| Candidate | Votes | % |
| 58,320 | 76.9 | |
| Jeryl Best | 17,541 | 23.1 |
|-| | colspan=5 |Democratic hold|-