| Election Name: | 1863 California gubernatorial election |
| Type: | presidential |
| Previous Election: | 1861 California gubernatorial election |
| Previous Year: | 1861 |
| Next Election: | 1867 California gubernatorial election |
| Next Year: | 1867 |
| Ongoing: | no |
| Election Date: | September 2, 1863 |
| Image1: | File:FrederickFerdinandLow (3x4) a.png |
| Nominee1: | Frederick Low |
| Party1: | National Union Party (United States) |
| Popular Vote1: | 64,283 |
| Percentage1: | 59.03% |
| Nominee2: | John G. Downey |
| Party2: | Democratic Party (United States) |
| Popular Vote2: | 44,622 |
| Percentage2: | 40.97% |
| Governor | |
| Before Election: | Leland Stanford |
| Before Party: | Republican Party (United States) |
| After Election: | Frederick Low |
| After Party: | Republican Party (United States) |
The 1863 California gubernatorial election was held on September 2, 1863, to elect the governor of California. Former governor John G. Downey was unsuccessful in his bid for reelection to a second, non-consecutive term, losing to former United States Representative Frederick Low. This was the state's first gubernatorial election for a four-year term; previous governors had only served two-year terms.
| County | Frederick Low National Union | John G. Downey Democratic | Scattering Write-in | Margin | Total votes cast | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| % | % | % | % | ||||||||||||||||
| Alameda | 1,404 | 63.59% | 804 | 36.41% | 0 | 0.00% | 600 | 27.17% | 2,208 | ||||||||||
| Amador | 2,245 | 52.10% | 2,064 | 47.90% | 0 | 0.00% | 181 | 4.20% | 4,309 | ||||||||||
| Butte | 1,876 | 55.73% | 1,490 | 44.27% | 0 | 0.00% | 386 | 11.47% | 3,366 | ||||||||||
| Calaveras | 2,278 | 52.89% | 2,029 | 47.11% | 0 | 0.00% | 249 | 5.78% | 4,307 | ||||||||||
| Colusa | 479 | 45.93% | 564 | 54.07% | 0 | 0.00% | -85 | -8.15% | 1,043 | ||||||||||
| Contra Costa | 1,064 | 66.58% | 534 | 33.42% | 0 | 0.00% | -530 | -33.17% | 1,598 | ||||||||||
| Del Norte | 184 | 54.76% | 152 | 45.24% | 0 | 0.00% | 32 | 9.52% | 336 | ||||||||||
| El Dorado | 3,210 | 60.01% | 2,139 | 39.99% | 0 | 0.00% | 1,071 | 20.02% | 5,349 | ||||||||||
| Fresno | 83 | 18.00% | 378 | 82.00% | 0 | 0.00% | -295 | -63.99% | 461 | ||||||||||
| Humboldt | 502 | 71.92% | 196 | 28.08% | 0 | 0.00% | 306 | 43.84% | 698 | ||||||||||
| Klamath | 204 | 50.62% | 199 | 49.38% | 0 | 0.00% | 5 | 1.24% | 403 | ||||||||||
| Los Angeles | 702 | 41.69% | 982 | 58.31% | 0 | 0.00% | -280 | -16.63% | 1,684 | ||||||||||
| Marin | 640 | 56.69% | 489 | 43.31% | 0 | 0.00% | 151 | 13.37% | 1,129 | ||||||||||
| Mariposa | 835 | 47.55% | 921 | 52.45% | 0 | 0.00% | -86 | -4.90% | 1,756 | ||||||||||
| Mendocino | 632 | 52.54% | 571 | 47.46% | 0 | 0.00% | 61 | 5.07% | 1,203 | ||||||||||
| Merced | 95 | 22.41% | 329 | 77.59% | 0 | 0.00% | -234 | -55.19% | 424 | ||||||||||
| Mono | 1,009 | 59.21% | 695 | 40.79% | 0 | 0.00% | 314 | 18.43% | 1,704 | ||||||||||
| Monterey | 522 | 50.73% | 507 | 49.27% | 0 | 0.00% | 15 | 1.46% | 1,029 | ||||||||||
| Napa | 898 | 57.64% | 660 | 42.36% | 0 | 0.00% | 238 | 15.28% | 1,558 | ||||||||||
| Nevada | 2,882 | 62.14% | 1,756 | 37.86% | 0 | 0.00% | 1,126 | 24.28% | 4,638 | ||||||||||
| Placer | 2,057 | 55.94% | 1,620 | 44.06% | 0 | 0.00% | 437 | 11.88% | 3,677 | ||||||||||
| Plumas | 1,288 | 62.71% | 766 | 37.29% | 0 | 0.00% | 522 | 25.41% | 2,054 | ||||||||||
| Sacramento | 3,553 | 64.64% | 1,944 | 35.36% | 0 | 0.00% | 1,609 | 29.27% | 5,497 | ||||||||||
| San Bernardino | 361 | 48.98% | 376 | 51.02% | 0 | 0.00% | -15 | -2.04% | 737 | ||||||||||
| San Diego | 116 | 46.77% | 132 | 53.23% | 0 | 0.00% | -16 | -6.45% | 248 | ||||||||||
| San Francisco | 9,261 | 62.94% | 5,452 | 37.06% | 0 | 0.00% | 3,809 | 25.89% | 14,713 | ||||||||||
| San Joaquin | 1,981 | 57.35% | 1,473 | 42.65% | 0 | 0.00% | 508 | 14.71% | 3,454 | ||||||||||
| San Luis Obispo | 260 | 54.28% | 219 | 45.72% | 0 | 0.00% | 41 | 8.56% | 479 | ||||||||||
| San Mateo | 834 | 71.04% | 340 | 28.96% | 0 | 0.00% | 494 | 42.08% | 1,174 | ||||||||||
| Santa Barbara | 481 | 77.08% | 143 | 22.92% | 0 | 0.00% | 338 | 54.17% | 624 | ||||||||||
| Santa Clara | 2,034 | 57.15% | 1,525 | 42.85% | 0 | 0.00% | 509 | 14.30% | 3,559 | ||||||||||
| Santa Cruz | 904 | 69.17% | 403 | 30.83% | 0 | 0.00% | 501 | 38.33% | 1,307 | ||||||||||
| Shasta | 936 | 60.27% | 617 | 39.73% | 0 | 0.00% | 319 | 20.54% | 1,553 | ||||||||||
| Sierra | 2,380 | 64.62% | 1,303 | 35.38% | 0 | 0.00% | 1,077 | 29.24% | 3,683 | ||||||||||
| Siskiyou | 1,053 | 51.29% | 999 | 48.66% | 1 | 0.05% | 54 | 2.63% | 2,053 | ||||||||||
| Solano | 1,521 | 57.50% | 1,124 | 42.50% | 0 | 0.00% | 397 | 15.01% | 2,645 | ||||||||||
| Sonoma | 1,700 | 49.82% | 1,712 | 50.18% | 0 | 0.00% | -12 | -0.35% | 3,412 | ||||||||||
| Stanislaus | 347 | 46.51% | 399 | 53.49% | 0 | 0.00% | -52 | -6.97% | 746 | ||||||||||
| Sutter | 718 | 51.40% | 679 | 48.60% | 0 | 0.00% | 39 | 2.79% | 1,397 | ||||||||||
| Tehama | 533 | 54.06% | 453 | 45.94% | 0 | 0.00% | 80 | 8.11% | 986 | ||||||||||
| Trinity | 785 | 56.52% | 604 | 43.48% | 0 | 0.00% | 181 | 13.03% | 1,389 | ||||||||||
| Tulare | 610 | 46.04% | 715 | 53.96% | 0 | 0.00% | -105 | -7.92% | 1,325 | ||||||||||
| Tuolumne | 1,813 | 49.31% | 1,864 | 50.69% | 0 | 0.00% | -51 | -1.39% | 3,677 | ||||||||||
| Yolo | 865 | 52.97% | 768 | 47.03% | 0 | 0.00% | 97 | 5.94% | 1,633 | ||||||||||
| Yuba | 1,989 | 58.81% | 1,393 | 41.19% | 0 | 0.00% | 596 | 17.62% | 3,382 | ||||||||||
| Soldiers | 4,159 | 96.74% | 140 | 3.26% | 0 | 0.00% | 4,019 | 93.49% | 4,299 | ||||||||||
| Total | 64,283 | 59.03% | 44,622 | 40.97% | 1 | 0.00% | 19,661 | 18.05% | 108,906 | ||||||||||