
He said heeding the warning would "avoid legal problems".
The state of emergency, imposed on Tuesday, bans gatherings of five or more people or any action inciting public disorder.
"If the candidates really want to hold a campaign rally, [they should] notify the commission or its local staff in advance," Ping said, "Candidates must be careful not to flout the emergency decree whenever they are on stage".
The director of the EC in Bangkok, Chainarong Tienmongkol, said candidates would be briefed next Friday on how to proceed with their campaigns during the state of emergency.
The election is on October 5 and candidates have until tomorrow to register. So far 11 have signed up to run for the capital's top job.
They include the last incumbent Apirak Kosayodhin, former deputy leader of the Chart Thai Party Chuwit Kamolvisit and former governor of the Mass Rapid Transit Authority Prapat Chongsanguan.
Apirak runs on the Democrat Party ticket and Prapat under the People Power Party banner.