- May 6 – 72-year-old South Carolina woman Mary J. Treacy is mortally injured in a three-vehicle crash on I-495 in Springfield. Treacy is taken to the Inova Fairfax Hospital, where she dies.
- May 16 – Kyle Alifom is sentenced to six years and eight months in prison by U.S. District Judge Claude M. Hilton for his role in the August 2013 overdose death of Emylee A. Lonczak in Vienna.
- May 17 – 20-year-old Domingo Eduardo Santiago Cuchil is stabbed and mortally wounded in Centreville. Santiago is taken to the Inova Fairfax Hospital, where he dies.
- May 19 – 24-year-old Jose Blanco-Calzadilla pleads guilty to voluntary manslaughter for fatally shooting 16-year-old Gerard Gomez at a party at the Residence Inn in Vienna on September 15, 2013.
- May 20 – 71-year-old Benfeng Liu is struck and killed as she attempts to cross Lee Highway near Trinity Parkway in Centreville.
- May 24 – 24-year-old Junior Abel Flores is stabbed and mortally injured in Springfield. Flores is found lying in the roadway near the intersection of Backlick Road and Highland Street and taken to the hospital, where he dies.
- May 27 – 34-year-old MaryAnn Brookie is killed in a fire that destroys her condo at 8228 Catbird Circle in the Gunston Corner neighborhood in Lorton.
- "Woman Killed in Fiery Crash at I-495 Express Lanes Ramp." INSIDENOVA.COM. Northern Virginia Media Services, 6 May 2014. Web. 07 May 2014.
- Cohen, Greg. "Fatal Accident Stymies Rush Hour Traffic on I-495." WUSA9.com. WUSA9, 7 May 2014. Web. 07 May 2014.
- Zapotosky, Matt. "Alifom Sentenced for Hiding Emylee Lonczak’s Body after Heroin Overdose." Washington Post. The Washington Post, 17 May 2014. Web. 18 May 2014.
- FCPD PIO. "Centreville Man Killed in Altercation." Web log post. Fairfax County Police Department News. Fairfax County Police Department, 19 May 2014. Web. 20 May 2014.
- Jouvenal, Justin. "Man Pleads Guilty in Killing of Fairfax County Teen." Washington Post. The Washington Post, 19 May 2014. Web. 27 Aug. 2016.
- Barton, Mary Ann. "Pedestrian Struck and Killed in Centreville." Centreville Patch. Patch.com, 21 May 2014. Web. 26 May 2014.
- FCPD PIO. "UPDATE: Homicide Victim Identified." Web log post. Fairfax County Police Department News. Fairfax County Police Department, 27 May 2014. Web. 9 June 2014.
- Fairfax County Fire and Rescue Department. Lorton Fire Victim Identified. Fairfax County Fire and Rescue Department News Releases. Fairfax County Fire and Rescue Department, 28 May 2014. Web. 29 May 2014.
|Fairfax County by Year: 2014|
|April 2014||·||May||·||June 2014|