| Competition: | 1. Liga |
| Season: | 1979–80 |
| Winners: | Group 1: FC Bulle Group 2: FC Laufen Group 3: FC Emmen Group 4: Mendrisiostar |
| Promoted: | FC Bulle Mendrisiostar |
| Relegated: | Group 1: FC Meyrin FC Visp Group 2: SC Düdingen FC Lengnau Group 3: FC Glattbrugg FC Unterstrass Group 4: SC Brühl FC Zug |
| Matches: | 4 times 182 and 3 deciders plus 13 play-offs |
| Prevseason: | 1978–78 |
| Nextseason: | 1980–81 |
The 1979–80 1. Liga was the 48th season of this league since its creation in 1931. At this time, the 1. Liga was the third tier of the Swiss football league system and it was the highest level of amateur football.
There were 56 clubs in the 1. Liga. These were divided into four regional groups, each with 14 teams. Within each group, the teams would play a double round-robin to decide their league position. Two points were awarded for a win. The four group winners and the four runners-up contested a first play-off round to decide the two promotion slots. The two last placed teams in each group were directly relegated to the 2. Liga (fourth tier).
| Club | Canton | Stadium | Capacity | |
|---|---|---|---|---|
| FC Bulle | Fribourg | Stade de Bouleyres | ||
| Étoile Carouge FC | Geneva | Stade de la Fontenette | ||
| FC Fétigny[1] | Fribourg | Stade Communal Fétigny | ||
| FC Leytron[2] | Valais | Stade Saint-Martin | ||
| ES FC Malley | Vaud | Centre sportif de la Tuilière | ||
| FC Martigny-Sports | Valais | Stade d'Octodure | ||
| FC Meyrin | Geneva | Stade des Arbères | ||
| FC Monthey | Valais | Stade Philippe Pottier | ||
| FC Montreux-Sports | Vaud | Stade de Chailly | ||
| FC Orbe[3] | Vaud | Stade du Puisoir | ||
| FC Renens[4] | Waadt | Zone sportive du Censuy | ||
| FC Stade Lausanne | Vaud | Centre sportif de Vidy | ||
| FC Stade Nyonnais | Vaud | Stade de Colovray | ||
| FC Visp[5] | Valais | Sportplatz Mühleye | ||
| Club | Canton | Stadium | Capacity |
|---|---|---|---|
| FC Allschwil[6] | Basel-Country | Im Brüel, Allschwil | |
| FC Aurore Bienne[7] | Bern | Tilleul-Linde | |
| SC Binningen | Basel-Country | Spiegelfeld | |
| FC Birsfelden[8] | Basel-Country | Sternenfeld | |
| US Boncourt[9] | Jura | Stade Communal Léon Burrus | |
| FC Boudry[10] | Neuchâtel | Stade des Buchilles | |
| FC Central Fribourg[11] | Fribourg | Guintzet | |
| SR Delémont | Jura | La Blancherie | |
| SC Düdingen | Fribourg | Stadion Birchhölzli | |
| FC Köniz[12] | Bern | Sportplatz Liebefeld-Hessgut | |
| FC Laufen | Basel-Country | Sportplatz Nau | |
| FC Lengnau[13] | Bern | Moos Lengnau BE | |
| FC Lerchenfeld[14] | canton of Bern | Sportanlagen Waldeck | |
| SV Muttenz | Basel-Country | Sportplatz Margelacker | |
The decider match for second place was played on 28 May in La Blancherie in Delémont SV Muttenz win after the penalty shoot-out and advance to play-offs. FC Aurore Bienne remain in the division.
| Club | Canton | Stadium | Capacity |
|---|---|---|---|
| FC Blue Stars Zürich[15] | Zürich | Hardhof | |
| SC Derendingen[16] | Solothurn | Heidenegg | |
| SC Emmen[17] | Lucerne | Sportanlage Feldbreite | |
| FC Emmenbrücke | Lucerne | Stadion Gersag | |
| FC Oberentfelden[18] | Aargau | Schützenrain | |
| FC Glattbrugg[19] | Zürich | Sportanlage Au | |
| FC Herzogenbuchsee[20] | Bern | Waldäcker | |
| FC Schaffhausen | Schaffhausen | Stadion Breite | |
| FC Solothurn | Solothurn | Stadion FC Solothurn | |
| FC Suhr[21] | Aargau | Hofstattmatten | |
| FC Sursee[22] | Lucerne | Stadion Schlottermilch | |
| FC Turicum[23] | Zürich | Hardhof | |
| FC Unterstrass[24] | Zürich | Steinkluppe | |
| FC Young Fellows Zürich | Zürich | Utogrund | |
The decider was played on 1 June in Baden. FC Herzogenbuchsee win and remain in the division. FC Glattbrugg are relegated to 2. Liga Interregional.
| Club | Canton | Stadium | Capacity | |
|---|---|---|---|---|
| FC Altstätten (St. Gallen)[25] | St. Gallen | Grüntal Altstätten | ||
| FC Balzers |  Liechtenstein | Sportplatz Rheinau | ||
| SC Brühl | St. Gallen | Paul-Grüninger-Stadion | ||
| FC Gossau | St. Gallen | Sportanlage Buechenwald | ||
| FC Ibach | Schwyz | Gerbihof | ||
| FC Locarno | Locarno, Ticino | |||
| Mendrisiostar | Ticino | Centro Sportivo Comunale | ||
| FC Morbio[26] | Ticino | Campo comunale Balerna | ||
| FC Rüti[27] | Zürich | Schützenwiese | ||
| FC Stäfa[28] | Zürich | Sportanlage Frohberg | ||
| FC Uzwil[29] | St. Gallen | Rüti | ||
| FC Vaduz | Liechtenstein | Rheinpark Stadion | ||
| SC Zug | Zug | Herti Allmend Stadion | ||
| FC Zug | Zug | Herti Allmend Stadion | ||
The decider was played on 1 June in Zürich. SC Zug win and remain in division. SC Brühl are relegated to 2. Liga Interregional.
FC Bulle win 5–3 on aggregate and continue to the finals. Mendrisiostar win 5–0 on aggregate and continue to the finals. FC Emmen win 3–2 on aggregate and continue to the finals. FC Laufen win 5–1 on aggregate and continue to the finals.
FC Bulle win 3–0 on aggregate and are promoted to 1980–81 Nationalliga B. FC Emmen remain in the division. 1st match abandonned after 6' due to rainfall: replay June 29 in Laufen. Mendrisiostar win 4–2 on aggregate and are promoted to 1980–81 Nationalliga B. FC Laufen remain in the division.