The 100-kg Soviet-made bomb was found near a kindergarten sandpit in a densely populated housing estate in the city of 100,000 people, some 65 kilometres southwest of Budapest.
The bomb contained 25 kg of explosives, Szekesfehervar county office head Norbert Dancs told a press conference.
"It's rare to find such a large bomb in an inhabited area of Hungary these days," Dancs said.
Cities and towns across Nazi-allied Hungary were bombed heavily during the final months of the war by US, British and Soviet forces, with Budapest in particular carpet-bombed on 37 occasions.
Yesterday police evacuated around 1,500 people in Budapest after a bomb was found during construction work at an apartment block near Buda Castle.
All the bombs have so far been secured without damages or injuries.