The killings came a day after a volunteer for the World Health Organisation's anti-polio campaign was shot dead in Pakistan's largest city, Karachi.
Five of the polio workers killed yesterday were also in Karachi. Four were women.
The attacks were co-ordinated and occurred simultaneously in three different places.
The government suspended the vaccination campaign in the wake of the shootings.
Gunmen on a motorcycle also shot dead a woman working on a government anti-polio campaign in a village near Peshawar.
The Taliban have spoken out against polio vaccination in recent months, claiming the health workers are acting as spies for the US and the vaccine itself causes harm. Militants in parts of Pakistan's tribal region have also stated the vaccination campaign cannot go forward until the US stops drone attacks.
The shootings in Karachi all took place in areas mainly populated by ethnic Pashtuns. The Taliban are a Pashtun-dominated movement, and many militants are reported to be hiding in these communities in Karachi.
Pakistan is one of only three countries where polio is endemic. The virus usually infects children living in unsanitary conditions, attacks the nerves and can kill or paralyse.