| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| O. Cordero Palacios | city | Provincia del Azuay | Ecuador | -2.80 | -78.97 | 8986 | 34048 |
| OCC (FRANCISCO DE ORELLANA) | airport | Ecuador | -0.46 | -76.99 | 834 | 0 | |
| Oasis | city | Provincia de Sucumbios | Ecuador | -0.45 | -76.10 | 780 | 85 |
| Obispopamba | city | Provincia de El Oro | Ecuador | -3.48 | -79.62 | 10373 | 2345 |
| Obraje | city | Provincia del Tungurahua | Ecuador | -1.30 | -78.52 | 7808 | 30906 |
| Ocampo | city | Provincia de Imbabura | Ecuador | 0.32 | -78.27 | 7686 | 34170 |
| Octavio Cordero | city | Provincia del Azuay | Ecuador | -2.80 | -78.97 | 8986 | 34048 |
| Octavio Cordero Palacios | city | Provincia del Azuay | Ecuador | -2.80 | -78.97 | 8986 | 34048 |
| Olalla | city | Provincia de Pichincha | Ecuador | -0.23 | -78.35 | 8763 | 25941 |
| Olan | city | Provincia de Manabi | Ecuador | -1.82 | -80.75 | 177 | 3787 |
| Olguín | city | Provincia de Cotopaxi | Ecuador | -1.05 | -78.62 | 8713 | 21675 |
| Olinda | city | Provincia del Guayas | Ecuador | -2.03 | -79.75 | 49 | 5759 |
| Oliva | city | Provincia de Pichincha | Ecuador | -0.25 | -79.18 | 1820 | 72712 |
| Olive | city | Provincia del Guayas | Ecuador | -2.12 | -79.85 | 9 | 87354 |
| Olivo | city | Provincia de Esmeraldas | Ecuador | 0.98 | -79.42 | 196 | 5189 |
| Olmedo | city | Provincia de Manabi | Ecuador | -1.42 | -80.22 | 469 | 6310 |
| Olmedo | city | Provincia del Guayas | Ecuador | -2.40 | -80.45 | 498 | 2567 |
| Olmedo | city | Provincia de Pichincha | Ecuador | 0.15 | -78.08 | 10570 | 2661 |
| Olmedo | city | Provincia de Loja | Ecuador | -3.95 | -79.67 | 5013 | 8319 |
| Olmedo | city | Provincia de Esmeraldas | Ecuador | 1.22 | -79.05 | 0 | 6480 |
| Olmedo | city | Provincia del Tungurahua | Ecuador | -1.33 | -78.55 | 8320 | 41509 |
| Olmedo Perdomo | city | Provincia de Esmeraldas | Ecuador | 0.72 | -80.08 | 1007 | 2542 |
| Olón | city | Provincia del Guayas | Ecuador | -1.77 | -80.77 | 203 | 3181 |
| Ona | city | Provincia del Azuay | Ecuador | -3.45 | -79.17 | 8277 | 2111 |
| Onashapa | city | Provincia del Azuay | Ecuador | -3.45 | -79.12 | 8572 | 2308 |
| Once de Noviembre | city | Provincia de Cotopaxi | Ecuador | -0.90 | -78.67 | 9304 | 31114 |
| Oncebi | city | Provincia de Los Rios | Ecuador | -1.40 | -79.32 | 2372 | 7052 |
| Oncevi | city | Provincia de Los Rios | Ecuador | -1.40 | -79.32 | 2372 | 7052 |
| Ontaneda | city | Provincia de Pichincha | Ecuador | -0.30 | -78.50 | 8572 | 311110 |
| Ontanon | city | Provincia de Imbabura | Ecuador | 0.33 | -78.22 | 7982 | 42999 |
| Opaluca | city | Provincia de Loja | Ecuador | -4.02 | -79.67 | 4094 | 6677 |
| Opar | city | Provincia del Canar | Ecuador | -2.73 | -78.83 | 9461 | 51466 |
| Opoluca | city | Provincia de Loja | Ecuador | -4.02 | -79.67 | 4094 | 6677 |
| Opote | city | Provincia del Chimborazo | Ecuador | -1.77 | -78.75 | 10875 | 11897 |
| Ordonez | city | Provincia del Azuay | Ecuador | -2.82 | -78.77 | 9041 | 24733 |
| Ordonez Laso | city | Provincia del Azuay | Ecuador | -2.82 | -78.77 | 9041 | 24733 |
| Ordoñes | city | Provincia de Pichincha | Ecuador | -0.35 | -78.43 | 8733 | 71715 |
| Ordoñez Lazo | city | Provincia del Azuay | Ecuador | -2.82 | -78.77 | 9041 | 24733 |
| Oretga | city | Provincia de Zamora Chinchipe | Ecuador | -3.55 | -78.93 | 4993 | 551 |
| Orianga | city | Provincia de Loja | Ecuador | -3.88 | -79.87 | 3188 | 1997 |
| Ornopata | city | Provincia del Canar | Ecuador | -2.80 | -78.92 | 8248 | 28703 |
| Orta | city | Provincia de Loja | Ecuador | -4.22 | -79.23 | 5859 | 3921 |
| Ortega | city | Provincia del Tungurahua | Ecuador | -1.23 | -78.53 | 8018 | 36543 |
| Ortega | city | Provincia del Azuay | Ecuador | -2.83 | -78.82 | 9235 | 23383 |
| Ortega | city | Provincia de Pichincha | Ecuador | -0.30 | -78.55 | 9990 | 488738 |
| Ortega Alto | city | Provincia de Zamora Chinchipe | Ecuador | -3.52 | -78.92 | 6322 | 306 |
| Ortega Bajo | city | Provincia de Zamora Chinchipe | Ecuador | -3.53 | -78.91 | 5892 | 370 |
| Ortencia | city | Provincia del Guayas | Ecuador | -2.05 | -79.42 | 606 | 10678 |
| Ortuno | city | Provincia de Cotopaxi | Ecuador | -0.72 | -78.63 | 10173 | 11789 |
| Osayacu | city | Provincia de Napo | Ecuador | -0.77 | -77.78 | 3431 | 447 |
| Oso | city | Provincia de Imbabura | Ecuador | 0.70 | -78.30 | 5511 | 1383 |
| Osorio | city | Provincia de Pichincha | Ecuador | -0.15 | -78.50 | 9274 | 538474 |
| Ostiones | city | Provincia de Esmeraldas | Ecuador | 1.02 | -79.32 | 193 | 2785 |
| Otavalo | city | Provincia de Imbabura | Ecuador | 0.23 | -78.27 | 8641 | 41922 |
| Otilia | city | Provincia del Guayas | Ecuador | -1.92 | -79.53 | 144 | 15315 |
| Oton | city | Provincia de Pichincha | Ecuador | -0.12 | -78.33 | 8156 | 23957 |
| Oton | city | Provincia de Pichincha | Ecuador | -0.03 | -78.23 | 10606 | 11816 |
| Otoncito | city | Provincia de Pichincha | Ecuador | -0.02 | -78.23 | 9711 | 12482 |
| Otono | city | Provincia del Guayas | Ecuador | -1.95 | -79.67 | 75 | 14132 |
| Otovalo | city | Provincia de Imbabura | Ecuador | 0.23 | -78.27 | 8641 | 41922 |
| Otón Llano | city | Provincia de Pichincha | Ecuador | -0.03 | -78.27 | 9826 | 13982 |
| Ovalo | city | Provincia de Pichincha | Ecuador | -0.37 | -78.40 | 8966 | 39825 |
| Ovejería | city | Provincia de Pichincha | Ecuador | -0.62 | -78.45 | 12906 | 2674 |
| Ovejería | city | Provincia del Carchi | Ecuador | 0.80 | -77.75 | 9639 | 46170 |
| Ovejo | city | Provincia del Carchi | Ecuador | 0.83 | -77.98 | 12562 | 2818 |
| Oyacachi | city | Provincia de Napo | Ecuador | -0.20 | -78.07 | 11200 | 768 |
| Oyambaro | city | Provincia de Pichincha | Ecuador | -0.20 | -78.32 | 9960 | 20233 |