The four were identified as Mehdi Zori, Houshang Kiani, Jamaloddin Jamali, and Abdol-Rahman Safar-Zehi were accused of instigating trouble and drug-related offences.
Iranian authorities routinely execute dissidents on the bogus charge of drug smuggling.
Sistan-va-Baluchistan Province is home to Baluchis, a predominantly Sunni Muslim ethnic minority.
Iran has witnessed escalating unrest since 2006 in areas populated by Baluchis, who complain of discriminatory and repressive policies by the theocratic regime.
In recent months, Iranian authorities have stepped up executions in the restive province in what many Baluchis believe is a response to a spate of attacks by dissidents on government and security officials.
A Baluchi group opposed to the government of Iran calling itself Jondollah has claimed responsibility for a string of armed attacks on government officials including an ambush in March on a government convoy, which left twenty-two security and provincial officials dead and at least seven, including the governor of the city of Zahedan, critically wounded.
