| Club: | Legia Warsaw |
| Season: | 2019-20 |
| Manager: | Aleksandar Vuković (from 9 April 2019) |
| Mgrtitle: | Manager |
| Chairman: | Dariusz Mioduski |
| Stadium: | Polish Army Stadium |
| League: | Ekstraklasa |
| League Result: | 1st |
| Cup1: | Polish Cup |
| Cup1 Result: | Semi-finals |
| Cup2: | UEFA Europa League |
| Cup2 Result: | Play-off round |
| League Topscorer: | Jarosław Niezgoda (14) |
| Season Topscorer: | Jarosław Niezgoda (14) |
| Prevseason: | 2018–19 |
| Nextseason: | 2020–21 |
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The 2019–20 Legia Warsaw season is the club's 103rd season of existence, and their 83rd in the top flight of Polish football.
| Player | From | Date | Source | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 26 | MF | align=left | Cafú | FC Metz | Transfer | €800,000 | 31 May 2019 | [2] | |
| 19 | GK | align=left |  Wojciech Muzyk | Olimpia Grudziądz | Transfer | €50,000 | 6 June 2019 | [3] | |
| 5 | DF | align=left | Igor Lewczuk | Bordeaux | Transfer | Free | 12 June 2019 | [4] | |
| 8 | MF | align=left |  Valerian Gvilia | FC Luzern | Transfer | €300,000 | 12 June 2019 | [5] | |
| 18 | MF | align=left | Arvydas Novikovas | Jagiellonia Białystok | Transfer | €300,000 | 27 June 2019 | [6] | |
| 82 | MF | align=left |  Luquinhas | CD Aves | Transfer | €400,000 | 4 July 2019 | [7] | |
| 37 | DF | align=left | Ivan Obradović | RSC Anderlecht | Transfer | Free | 11 July 2019 | [8] |
See main article: 2019–20 Ekstraklasa.
See main article: 2019–20 Polish Cup.
See main article: 2019–20 UEFA Europa League.
Legia Warsaw won 4–0 on aggregate.----
Legia Warsaw won 1–0 on aggregate.----
Legia Warsaw won 2–0 on aggregate.----
Legia Warsaw lost 0–1 on aggregate.