All workers and visitors seeking access to BHP workplaces in Australia will be required to be fully vaccinated against COVID-19 from January 31, 2022.
BHP workplaces in New South Wales, including the Mt Arthur coal mine, will introduce the measures sooner, considering local risk factors.
It follows announcements from the Victorian and Western Australian governments in the past week which mandate vaccines for mineworkers.
The company has been considering mandating vaccination since at least August.
"The science is clear that widespread vaccination saves lives," BHP Minerals Australia president Edgar Basto said.
"In line with government guidance, we recognise the path forward is through widespread vaccination in Australia and we are looking at a range of practical ways to support that while protecting communities and workforces.
"We have undertaken a thorough assessment and believe that this is the right path forward to protect the health of our people, their families and the communities where we operate - including remote Indigenous communities - while continuing to safely run our operations. We know this raise will questions for some, and we will work closely with our workforce as we go through the process of implementing these controls at our workplaces."
The Australian Manufacturing Workers' Union and Mining and Energy Union spoke out, saying they did not support the decision.
AMWU Queensland and Northern Territory secretary Rohan Webb said vaccination was a personal health matter, and not a decision for employers to make.
"Decisions regarding vaccinations should be between the individual and medical professionals, not bosses," he said.
"Workers should be armed with accurate, reliable information regarding vaccination and not be forced to be vaccinated on direction by their employer.
"The best way to increase vaccination rates in our community is through education, not mandates.
"We have repeatedly called on BHP to engage in genuine consultation with their workforce and Unions about any policy they intended to introduce, this has never occurred.
"On the issue of mandatory vaccination, workers can rest assured the AMWU will defend their rights."
Webb said the AMWU was seeking legal advice.
Mining and Energy Union Queensland district president Stephen Smyth said vaccination should be voluntary.
"BHP must engage in genuine consultation with the workforce. Some of our immediate concerns include fair treatment of casuals and contractors on BHP sites - keeping in mind that a minority of workers on BHP's Queensland mine sites are direct employees; support for workers with a genuine medical exemption and paid time for workers to get vaccinated or in case of experiencing vaccine-related side-effects.
"Our priority is protecting our members' jobs, rights and working conditions as we work through the workforce and legal implications of BHP's announcement."