Elections to Purbeck District Council were held on 7 May 1998. One third of the council was up for election and the council stayed under no overall control.
After the election, the composition of the council was:
| Party | Seats | Gains | Losses | Net gain/loss | Seats % | Votes % | Votes | +/− | |
|---|---|---|---|---|---|---|---|---|---|
| Independent | 4 | 0 | 50.0 | ||||||
| Conservative | 3 | +3 | 37.5 | ||||||
| Liberal Democrats | 1 | -3 | 12.5 | ||||||