| Competition: | Segunda División |
| Season: | 1945–46 |
| Winners: | Sabadell |
| Promoted: | Sabadell Deportivo La Coruña |
| Relegated: | Jerez Salamanca Ceuta |
| League Topscorer: | José Saras Mariano Uceda (20 goals) |
| Best Goalkeeper: | Juan Acuña (1.08 goals/match) |
| Biggest Home Win: | (30 September 1945) (2 December 1945) (31 March 1946) |
| Biggest Away Win: | (21 October 1945) |
| Highest Scoring: | (7 October 1945) (27 January 1946) |
| Matches: | 182 |
| Total Goals: | 605 |
| Prevseason: | 1944–45 |
| Nextseason: | 1946–47 |
The 1945–46 Segunda División season was the 15th since its establishment and was played between 23 September 1945 and 31 March 1946.
14 teams joined the league, including three relegated from the 1944–45 La Liga and three promoted from the 1944–45 Tercera División.
| Goalscorers | Goals | Team |
|---|---|---|
| 20 | Real Santander | |
 Mariano Uceda | 20 | Zaragoza |
| Luis Barceló | 14 | Gimnástico |
| Antonio Vázquez | 13 | Sabadell |
| Trompi | 13 | Granada |
| Goalkeeper | Goals | Matches | Average | Team | |
|---|---|---|---|---|---|
| Juan Acuña | 28 | 26 | Deportivo La Coruña | ||
| Ricardo Pujol | 29 | 26 | Sabadell | ||
| Luis Martín | 27 | 24 | Real Córdoba | ||
| Román Galarraga | 28 | 23 | Real Sociedad | ||
| José María Martí | 28 | 20 | Granada |