The government says the officers are acting illegally
The Prison Officers' Association's strike comes after it pulled out of a no-strike agreement with government.
Officers in Leeds, Liverpool, Cardiff, Birmingham, East Anglia and London are among those who have stopped working.
The government is seeking a High Court injunction to stop the "illegal" strike which Justice Secretary Jack Straw has called "wholly unjustifiable".
The first step in that process - the serving of a legal notice to the POA for officers to return to work - has been taken.
Mr Straw said officials had approached the POA on Tuesday to organise a meeting.
The strike, which was announced at 0600 BST - an hour before action began, is the first national walkout in the association's 68-year history.
The Prison Officers' Association (POA), which has 28,000 members, said up to 90% of its members who had been due on duty in had joined the strike.
It said the walkout had been "widespread and unprecedented" and that there was "lockdown" - where prisoners are confined to their cells - at most prisons.
Affected prisons include:
Birmingham prison where a mass outdoor meeting has taken place and all 1,450 prisoners are locked down
Bristol prison where more than 120 officers joined a picket line after serving breakfast to inmates
Wormwood Scrubs prison, west London, where the 1,300 prisoners are being looked after by eight governors
Manchester Prison - formerly known as Strangeways - where plans are in place to serve packed lunches and dinners to inmates in their cells
Cardiff prison where inmates locked in their cells have taunted officers striking in the car park with shouts of "you're breaking the law"
Dartmoor, Exeter and Channings Wood in south-west England
Wakefield prison, where prisoners include Soham murderer Ian Huntley
Frankland high-security prison, County Durham, where a handful of striking officers volunteered to go back to work because of the danger posed by inmates
Prison safety
The Ministry of Justice said the walkout was a breach of the Industrial Relations Act.
Mr Straw said in a statement that contingency plans were in place to maintain security in prisons where officers had gone on strike.
At my request yesterday, my office asked for a meeting with senior officers of the POA
Jack Straw
"Our first concern in this situation is to protect the public," he added.
"Ministers have met with the POA on a regular basis in recent weeks and were due to meet next month.
"Indeed, at my request yesterday, my office asked for a meeting with senior officers of the POA."
Prisoners are being kept in their cells at the moment.
The government says the officers are acting illegally
It is believed police may have to be drafted in to ensure the safety of inmates.
The walkout follows a POA national ballot of members two weeks ago.
Some 87% of the prison officers who voted endorsed industrial action "up to and including strike".
An independent pay review body recommended a 2.5% pay rise but the government staged that rise as 1.5% in April and a further 1% in November.
Pay row
The POA says that, due to inflation, this reduces the value of the award, making it a below-inflation pay increase.
But, after the ballot results, a Ministry of Justice spokeswoman said: "Pay rises for those at the top end of their pay scales have been below inflation for two years.
Surely we should be treated as well, if not better, than the prisoners we look after
Colin Moses
POA
"But those still rising on the incremental pay scales are receiving above inflation rises."
Prison Officers' Association (POA) general secretary Brian Caton said the government and the Prison Service had been told of the result of the ballot and that meetings had been requested.
"None of those meetings have happened and that has caused our membership to call for strike action which we have taken today."
Chairman Colin Moses said the decision to strike had been taken "after two years of frustration and two years of below-inflation pay awards".
"Surely we should be treated as well, if not better, than the prisoners we look after."
'Cross and fed-up'
Prison Governors' Association chairman Charles Bushell told BBC News that the majority of prisoners would become "cross and fed-up" but would "control themselves", he said.
"Equally, we know that there is a minority - quite a sizeable minority in some places - who will get cross and will find it difficult."
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Mark Leech, founder of the Prisons Handbook and a commentator on the penal system, said striking officers were "effectively taking prisoners hostage through this action".
"Every part of prison life comes down to the prison officers," he told the BBC News website.
"Visits will be cancelled, education and offending behaviour courses will not be running."
Some crown courts in England and Wales reported that prisoners due to appear had not been delivered while others reported no problems.
The Northern Ireland Prison Service said its prisons were unaffected by the action.
Entrada de la Wormwood Scrubs Prison

Oficiales de las prisiones se dieron a la huelga en Reino Unido comenzando a las 7:00 a.m. (BST) de hoy. La huelga comenzó por un desacuerdo sobre el payroll.

La huelga, sin embargo, era ilegal y el Ministerio de Justicia emitió un requerimiento judicial de la corte suprema contra la huelga.

La huelga afectó a todas las prisioneros; varios prisioneros están en ''lockdown'', que significa que aquellos que conviven en una celda están encerrado en ellas.

Se reportó incluso que tres prisioneros habían llegado al techo de la Prisión de Liverpool, pero la situación fue contenida.

En Wormwood Scrubs Prison, cerca de 745 prisioneros fueron controlados por tan sólo 20 oficiales.

En Cardiff, los oficiales en huelga incluso fueron burlados por los prisioneros que gritaban: "Están rompiendo la ley".

La huelga fue suspendida por la Asociación de Oficiales de Prisiones (POA por sus siglas en inglés), luego de haber desafiado el requerimiento de justicia del Ministerio.