20. TRIVANDRUM
Total Votes: 621533
Votes Polled: 448586
Invalid Votes: 14866
| Name of the Candidate | Party | Votes | Percentage |
| M. N. GOVINDAN NAIR | CPI | 244277 | 56.32 |
| P. VISWAMBHARAN | BLD | 174455 | 40.22 |
| J. M. DAICY | IND | 14866 | 3.43 |
| Total | 433598 | 99.97 | |
Mr. M. N. GOVINDAN NAIR (CPI) elected with a margin of 69822 votes.