| Competition: | OB I |
| Season: | 2005–06 |
| Winners: | Honvéd |
| Continentalcup1: | Euroleague |
| Continentalcup1 Qualifiers: | Honvéd Vasas Eger |
| Continentalcup2: | LEN Cup |
| Continentalcup2 Qualifiers: | Szeged Újpest |
| Prevseason: | 2004–05 |
| Nextseason: | 2006–07 |
2005–06 Országos Bajnokság I (men's water polo) was the 100th water polo championship in Hungary.
| Team | M | W | D | L | G+ | G− | P | |
|---|---|---|---|---|---|---|---|---|
| 1. | Domino-Bp. Honvéd | 22 | 21 | 0 | 1 | 362 | 160 | 42 |
| 2. | TEVA-Vasas SC-Plaket | 22 | 19 | 1 | 2 | 287 | 159 | 39 |
| 3. | Brendon-Fenstherm-ZF-Egri VK | 22 | 18 | 1 | 3 | 316 | 203 | 37 |
| 4. | Szeged-Beton VE | 22 | 12 | 4 | 6 | 233 | 178 | 28 |
| 5. | Újpesti TE-VB Leasing | 22 | 13 | 2 | 7 | 254 | 195 | 28 |
| 6. | Betonút-Ferencvárosi TC | 22 | 11 | 1 | 10 | 243 | 183 | 23 |
| 7. | Szolnoki VSC | 22 | 7 | 4 | 11 | 200 | 237 | 18 |
| 8. | Szentesi VK | 22 | 8 | 1 | 13 | 178 | 227 | 17 |
| 9. | Pécsi VSK-Fűszért | 22 | 7 | 0 | 15 | 185 | 239 | 14 |
| 10. | BVSC | 22 | 6 | 0 | 16 | 191 | 253 | 12 |
| 11. | OSC-Kaposvár | 22 | 2 | 2 | 18 | 167 | 318 | 6 |
| 12. | Neptun VSC | 22 | 0 | 0 | 22 | 132 | 396 | 0 |
| Championship Playoff | ||
| European competition Playoff | ||
| Relegation Playoff |