Opposition politicians and penal reform campaigners have blamed prison overcrowding for a 37 per cent rise in the number of inmates killing themselves.
Figures from the Ministry of Justice showed that 92 prisoners committed suicide in 2007, up from 67 in 2006.
Previous figures had suggested the number of prison suicides were falling, with 78 suicides in 2005 and 95 in 2004.
The number of female self-inflicted deaths increased by 133 per cent, with eight women killing themselves in custody in 2007 compared to three in 2006.
Shadow justice secretary Nick Herbert said: "Rising prison suicides are a terrible indictment of the government's mismanagement of the prisons system.
"Ministers ignored repeated warnings about inadequate prison capacity, they allowed the jails to become ever more overcrowded, and these tragic deaths are the inevitable and avoidable consequence."
Frances Crook, the director of the Howard League for Penal Reform, said the figures highlighted the "human cost of the prisons crisis".
"The prison service has taken great strides in suicide prevention in recent years but it is all for naught when the system is on its knees with record overcrowding," she added.
"Staff and resources are strained to the limit coping with an ever-swelling prison population rife with mental health problems, drug and alcohol addiction and histories of neglect and abuse.
"When government ministers consider the shame of our failing prison system, a system currently facing three per cent budget cuts despite the fact it is expected to house more people than ever before, the deaths of these 92 men, women and children should sit uneasily on their consciences."
However, a Ministry of Justice spokesman denied the allegations, saying: "There is no agreed evidence that overcrowding exacerbates levels of self-harm in prison."
And prisons minister Maria Eagle said the government was "determined to prevent deaths in custody".
Announcing a review of how to help offenders with mental health problems, she said: "I sincerely regret this year's increase in self-inflicted deaths after the significant decreases of recent years."
