Mário Sauer (born 15 May 2004) is a Slovak professional footballer who plays as a midfielder for French club Toulouse.
Sauer made his Fortuna Liga debut for à ½ilina against Spartak Trnava on 16 May 2021. He came on in the second half replacing Vahan Bichakhchyan.
On 22 May 2025, Sauer signed with Toulouse in France.
Sauer played for the Slovakia U-19 side alongside his younger brother, Leo Sauer. Both were selected for the Slovakia U-20 side to compete at the 2023 FIFA U-20 World Cup.