Zardari is the widower of Benazir Bhutto, the first female Prime Minister of an Islamic nation, who was assassinated in 2007. He has long faced corruption allegations.
Five police officers arrested Zardari, 63, at his home on charges related to suspicious transactions worth 4.4 billion Pakistani rupees (about $29 million) allegedly carried out through bank accounts in other people's names.
The former President, who served from 2008 to 2013, is being held by the National Accountability Bureau (NAB) and is due to appear Tuesday in court, a spokesperson for the anti-corruption body said.
Nationwide demonstrations will be held Tuesday to protest Zardari's arrest and an emergency consultative meeting of the Pakistan Peoples Party (PPP) will be held to discuss his legal options, party spokesman Murtaza Wahab said.
The PPP's official Twitter account said Zardari "handed himself into the NAB custody as a mark of protest against the unjust and unfair treatment being meted out to him here on Monday."