Kase (written: 加瀬) is a Japanese surname. Notable people with the surname include:
Hideaki Kase (born 1936), Japanese diplomatic critic
Jiro Kase (born 1954), Japanese judoka
Kanako Kase, Japanese professional racing cyclist
Max Kase (1897–1974), American newspaper editor
Ryō Kase (born 1974), Japanese actor
Shun'ichi Kase (1897–1956), Japanese diplomat
Taiji Kase (1929–2004), Japanese karate master
Toshikazu Kase (1903–2004), Japanese diplomat
Yasuyuki Kase (born 1971), Japanese voice actor