| Club: | Panathinaikos |
| Season: | 2019–20 |
| Manager: | Giorgos Donis |
| Chairman: | Manos Mavrokoukoulakis |
| League: | Super League Greece |
| League Result: | 4th |
| Cup1: | Greek Cup |
| Cup1 Result: | Quarter-finals |
| League Topscorer: | Federico Macheda (14) |
| Season Topscorer: | Federico Macheda (15) |
| Stadium: | Olympic Stadium |
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| Prevseason: | 2018–19 |
| Nextseason: | 2020–21 |
The 2019–20 Panathinaikos season was the club's 61st consecutive season in Super League Greece. They also competed in the Greek Cup.
| Date | Pos. | Name | From | Fee | ||
|---|---|---|---|---|---|---|
| 12 July 2019 | FW |  Christian Konan | Free agent | Free Transfer | [1] | |
| 18 July 2019 | MF | Dimitris Kolovos |  Omonia | Free Transfer | [2] | |
| 5 August 2019 | DF | João Nunes |  Lechia Gdańsk | Free Transfer | [3] | |
| 23 July 2019 | FW |  Yohan Mollo | Sochaux | Free Transfer | [4] | |
| 13 August 2019 | FW | Uffe Bech | Hannover 96 | Free Transfer | [5] | |
| 28 August 2019 | FW |  Juan José Perea | FC Porto U19 | Free Transfer | ||
| 29 August 2019 | DF | Bart Schenkeveld |  Melbourne City FC | Free Transfer | ||
| 12 September 2019 | MF |  Fausto Tienza | Extremadura UD | Free Transfer |
| Date | Pos. | Name | To | Fee | |
|---|---|---|---|---|---|
| 30 June 2019 | MF |  Ergys Kaçe | PAOK | End of Loan | |
| DF |  Ousmane Coulibaly |  Al-Wakrah | Free | ||
| DF | Konstantinos Valmas | Veria | Free | ||
| MF | Christos Kountouriotis |  Zemplín Michalovce | Free | ||
| MF | Dimos Chantzaras | Veria | Free | ||
| MF |  Omri Altman | Hapoel Tel Aviv | Free | [7] |
| Date | Pos. | Name | T | ||
|---|---|---|---|---|---|
| 15 July 2019 | FW | Mark Sifneos | Apollon Larissa | ||
| 16 August 2019 | MF | Adriano Skenterai | Ethnikos Piraeus | [8] |
See main article: 2019–20 Super League Greece.
See main article: 2019–20 Greek Football Cup.