| Club: | FC Basel |
| Season: | 1965–66 |
| Chairman: | Lucien Schmidlin |
| Manager: | Helmut Benthaus |
| Stdtitle: | Ground |
| Stadium: | Landhof or St. Jakob Stadium, Basel |
| League: | Nationalliga A |
| League Result: | 6th |
| Cup1: | Swiss Cup |
| Cup1 Result: | Semi-final |
| Cup2: | Inter-Cities Fairs Cup |
| Cup2 Result: | Second round |
| Cup3: | Cup of the Alps |
| Cup3 Result: | Group stage |
| League Topscorer: | Roberto Frigerio (15) |
| Season Topscorer: | Roberto Frigerio (22) |
| Highest Attendance: | 10,000 on 24.10.1965 vs Lausanne-Sport and on 6.03.1966 vs Servette |
| Lowest Attendance: | 3,000 on 21.11.1965 vs Young Fellows Zürich |
| Average Attendance: | 6,200 |
| Prevseason: | 1964–65 |
| Nextseason: | 1966–67 |
The 1965–66 season was Fussball Club Basel 1893's 72nd season in their existence. It was their 20th consecutive season in the top flight of Swiss football after their promotion in the 1945–46 season. They played their home games either in the traditional stadium Landhof or in their new venue the St. Jakob Stadium. Lucien Schmidlin was club chairman for the fourth consecutive year.
To the beginning of the season Helmut Benthaus transferred in from 1. FC Köln and became player-coach. He replaced Jiří Sobotka as team manager, who went on to manage the Swiss national team. Benthaus was a graduate of the German Sport University Cologne and an experienced player trainer. Two seasons earlier Benthaus had won the 1963–64 Bundesliga as player-manager with Köln. Benthaus used his first season with Basel to observe, feel and classify. One of the biggest changes that he made, with the agreement of the board of directors, was introduce semi-professionalism.
There were only a few minor changes to the squad, Rade Ognjanović transferred to Grenchen and Heinz Sartor transferred to Offenburger FV. Three players stepped back from Nationalliga A football, Carlo Porlezza, Mario Grava and Fernando Von Krannichfeldt went to play for the reserve team. As replacements three youngsters came from the youth team and three more from the reserve team.
Fourteen teams contested the 1965–66 Nationalliga A. These were the top 12 teams from the previous 1964–65 season and the two newly promoted teams Urania Genève Sport and Young Fellows Zürich. Basel finished the season in sixth position with 27 points. They ended the championship with ten wins, seven draws and nine defeats in their 26 matches. They scored 64 goals and conceded 57.[1] Top league goal scorer was Roberto Frigerio with 15 goals, ahead of Karl Odermatt who scored 11 and Helmut Hauser with 10 goals. Basel played 15 Test games, winning ten, one draw and losing four. Roberto 'Mucho' Frigerio was also the top scorer in these games, with 16 goals in just 13 games. Alone in the match against Black Stars Basel he managed to net the ball six times.[2]
In the Swiss Cup Basel started in the round of 32 on 7 November 1965, with a home win against Biel-Bienne. In the next round they played at home against Luzern with a 3–1 win. In the next round they were drawn away in the Wankdorf Stadium, Bern, against Young Boys. This ended in a 2–1 victory. In the semi-final they were drawn at home against Servette but were defeated 1–3. Zürich won the final and completed the double.[3]
In the 1965–66 Inter-Cities Fairs Cup Basel were drawn against Spanish team Valencia, but were beaten twice. In the Cup of the Alps Basel were drawn in the same group as Catania, S.S.C. Napoli, Juventus and Spal Ferrara. All four games ended in a defeat.
See main article: 1965–66 Nationalliga A.
See main article: Swiss Cup.
See main article: Inter-Cities Fairs Cup.
See main article: 1965–66 Inter-Cities Fairs Cup.
Valencia won 8–2 on aggregate.
See main article: Cup of the Alps.