| Election Name: | 1998 California State Assembly election |
| Country: | California |
| Type: | legislative |
| Ongoing: | no |
| Previous Election: | 1996 California State Assembly election |
| Previous Year: | 1996 |
| Next Election: | 2000 California State Assembly election |
| Next Year: | 2000 |
| Seats For Election: | All 80 seats in the California State Assembly |
| Majority Seats: | 41 |
| Leader1: | Antonio Villaraigosa |
| Party1: | California Democratic Party |
| Leaders Seat1: | 45th–Los Angeles |
| Last Election1: | 43 seats, 49.42% |
| Seats1: | 48 |
| Seat Change1: | 5 |
| Popular Vote1: | 4,106,175 |
| Percentage1: | 52.65% |
| Leader2: | Bill Leonard (retired as leader) |
| Party2: | California Republican Party |
| Leaders Seat2: | 63rd–San Bernardino |
| Last Election2: | 37 seats, 46.07% |
| Seats2: | 32 |
| Seat Change2: | 5 |
| Popular Vote2: | 3,494,503 |
| Percentage2: | 44.81% |
| Speaker | |
| Posttitle: | Elected Speaker |
| Before Election: | Antonio Villaraigosa |
| Before Party: | California Democratic Party |
| After Election: | Antonio Villaraigosa |
| After Party: | California Democratic Party |
The 1998 California State Assembly elections were held on November 3, 1998. California's State Assembly in its entirety comes up for election in even numbered years. Each seat has a two-year term and members are limited to three 2-year terms (six years). All 80 biennially elected seats in the Assembly were up for election this year. Democrats retained control of the Assembly, gaining five Republican-held seats in the process.
| California State Assembly elections, 1998 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Party | Votes | Percentage | Incumbents | Open | Before | After | Special | +/– | ||
| Democratic | 4,106,175 | 52.65% | 32 | 11 | 43 | 48 | 47 | +4 | ||
| Republican | 3,494,503 | 44.81% | 23 | 14 | 37 | 32 | 32 | -5 | ||
| Libertarian | 144,427 | 1.85% | 0 | 0 | 0 | 0 | 0 | 0 | ||
| Natural Law | 23,384 | 0.30% | 0 | 0 | 0 | 0 | 0 | 0 | ||
| Peace and Freedom | 19,362 | 0.25% | 0 | 0 | 0 | 0 | 0 | 0 | ||
| Reform | 4,256 | 0.05% | 0 | 0 | 0 | 0 | 0 | 0 | ||
| Green | 4,093 | 0.05% | 0 | 0 | 0 | 0 | 1 | +1 | ||
| American Independent | 2,678 | 0.03% | 0 | 0 | 0 | 0 | 0 | 0 | ||
| Invalid or blank votes | 842,620 | 9.75% | — | — | — | — | — | — | ||
| Totals | 8,641,498 | 100.00% | 55 | 25 | 80 | 80 | 80 | — | ||
| 48 | 32 | |
| Democratic | Republican | |
Final results from the California Secretary of State:[1]
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