May 30 is the 150th day of the year (151st in leap years). There are 215 days remaining.
- 1938 — Märt Ringmaa is born.
- 1947 — Robert George Clements died.
- 1953 — John Paul Phillips is born.
- 1958 — John Edward Brewer is born.
- 1969 — Susan Margarite Davis and Elizabeth Perry is allegedly murdered by Ted Bundy (suspected victim).
- 1976 — Robert Frederick Carr is apprehended.
- 1985 — Carol Kyle and her son are attacked by Richard Ramirez.
- 1985 — DeAngelo Martin is born.
- 1987 — Miyuki Ishikawa died.
- 1988 — Gary Ridgway's victim, Debra Lorraine Estes, is found.
- 1999 — Hardee Schmidt is murdered by Sean Vincent Gillis.
- 2001 — Richard Rogers is apprehended.
- 2005 — Kim Young-soon is murdered by Jeong Nam-gyu.
- 2007 — Amarjeet Sada is apprehended.