| Population Change 1990-2000 | ||||
| County or Municipality | 2000 Population | 1990 Population | Population Change | Percent Change |
| Pennsylvania | 12 281 054 | 11 881 643 | 399 411 | 3.4 |
| Huntingdon County | 45 586 | 44 164 | 1 422 | 3.2 |
| Alexandria borough | 401 | 411 | - 10 | - 2.4 |
| Barree township | 460 | 450 | 10 | 2.2 |
| Birmingham borough | 91 | 109 | - 18 | - 16.5 |
| Brady township | 1 035 | 1 053 | - 18 | - 1.7 |
| Broad Top City borough | 384 | 331 | 53 | 16.0 |
| Carbon township | 428 | 438 | - 10 | - 2.3 |
| Cass township | 1 062 | 998 | 64 | 6.4 |
| Cassville borough | 152 | 183 | - 31 | - 16.9 |
| Clay township | 920 | 921 | - 1 | - 0.1 |
| Coalmont borough | 128 | 109 | 19 | 17.4 |
| Cromwell township | 1 632 | 1 500 | 132 | 8.8 |
| Dublin township | 1 280 | 1 119 | 161 | 14.4 |
| Dudley borough | 192 | 232 | - 40 | - 17.2 |
| Franklin township | 447 | 466 | - 19 | - 4.1 |
| Henderson township | 972 | 933 | 39 | 4.2 |
| Hopewell township | 587 | 540 | 47 | 8.7 |
| Huntingdon borough | 6 918 | 6 843 | 75 | 1.1 |
| Jackson township | 882 | 816 | 66 | 8.1 |
| Juniata township | 553 | 429 | 124 | 28.9 |
| Lincoln township | 319 | 320 | - 1 | - 0.3 |
| Logan township | 703 | 684 | 19 | 2.8 |
| Mapleton borough | 473 | 529 | - 56 | - 10.6 |
| Marklesburg borough | 216 | 165 | 51 | 30.9 |
| Mill Creek borough | 351 | 392 | - 41 | - 10.5 |
| Miller township | 514 | 474 | 40 | 8.4 |
| Morris township | 416 | 415 | 1 | 0.2 |
| Mount Union borough | 2 504 | 2 878 | - 374 | - 13.0 |
| Oneida township | 1 129 | 1 085 | 44 | 4.1 |
| Orbisonia borough | 425 | 447 | - 22 | - 4.9 |
| Penn township | 1 054 | 956 | 98 | 10.3 |
| Petersburg borough | 455 | 469 | - 14 | - 3.0 |
| Porter township | 1 917 | 1 942 | - 25 | - 1.3 |
| Rockhill Furnace borough | 414 | 421 | - 7 | - 1.7 |
| Saltillo borough | 343 | 347 | - 4 | - 1.2 |
| Shade Gap borough | 97 | 113 | - 16 | - 14.2 |
| Shirley township | 2 526 | 2 494 | 32 | 1.3 |
| Shirleysburg borough | 140 | 140 | 0 | 0.0 |
| Smithfield township | 4 466 | 4 181 | 285 | 6.8 |
| Springfield township | 612 | 507 | 105 | 20.7 |
| Spruce Creek township | 263 | 281 | - 18 | - 6.4 |
| Tell township | 648 | 551 | 97 | 17.6 |
| Three Springs borough | 445 | 422 | 23 | 5.5 |
| Todd township | 1 004 | 889 | 115 | 12.9 |
| Union township | 1 005 | 992 | 13 | 1.3 |
| Walker township | 1 747 | 1 515 | 232 | 15.3 |
| Warriors Mark township | 1 635 | 1 375 | 260 | 18.9 |
| West township | 528 | 572 | - 44 | - 7.7 |
| Wood township | 713 | 727 | - 14 | - 1.9 |
| Source: U.S. Census Bureau | Prepared by: Pennsylvania State Data Center | |||