A spokesman of the banned terror group claimed responsibility for the brutal attack.
The four polio workers including three women were attacked on Wednesday near Eastern Bypass area of Quetta city when they were going to a health centre.
An anti-polio vaccination campaign was launched amid tight security in 11 districts of Balochistan earlier this month.
Pakistan government has come under severe criticism for doing little to eradicate the virus which is a threat to the world.
The Taliban consider polio medicine a conspiracy by the West to sterile Muslims. Peshawar is considered as hub of polio virus.
Polio is still endemic in Pakistan, Afghanistan and Nigeria. The World Health Organisation in May imposed travel restriction on Pakistan.
