Yannick Käser (born 3 July 1992 in Rheinfelden, Aargau) is a Swiss swimmer, specializing in breaststroke events.

[2][1] Kaeser made his international debut at the 2010 Summer Youth Olympics in Singapore, where he placed sixth in the 200 m breaststroke with his personal best of 2:17.78.

[4] In 2011, he cleared the 2:10 barrier to set a short-course Swiss record of 2:09.99 in the same stroke at the European Championships in Szczecin, Poland.

[5] Kaeser qualified for the men's 200 m breaststroke at the 2012 Summer Olympics in London, by breaking a long-course Swiss record and eclipsing a FINA B-cut of 2:12.09 from the European Championships in Debrecen, Hungary.

[6][7] He challenged seven other swimmers on the fourth heat, including top medal favorites Clark Burckle of the United States and Ryo Tateishi of Japan.