The authorities say castrations are done in accordance with the law
The Czech Republic has been strongly criticised by Europe's leading human rights body for continuing to surgically castrate male sex offenders.
The Council of Europe said castrations had sometimes been performed without warnings of side effects and on men not capable of making an informed decision.
Those requesting castration feared life in jail if they did not do so, it said.
The Czech government says 94 procedures have been performed in the past 10 years, all in accordance with its laws.
A further 300 Czech men have undergone chemical castration - involving the injection of drugs that suppress the production of male hormones - since 2000, according to government figures.
But the Council of Europe said Czech officials had provided "inexact information" on the numbers of those undergoing the procedures.
BBC Europe reporter Dominic Hughes says surgical castration - under which part of the testicles is removed - has been abandoned in many other countries because it is not clear whether it is effective in treating sex offenders.
Other countries, including Poland, Italy and France, seeking ways of dealing with violent sex offenders and paedophiles, have investigated using chemical castration methods.
But in the past decade the authorities in the Czech Republic have continued to carry out the surgical procedure, which the Council of Europe's Committee for the Prevention of Torture said amounted to "degrading treatment".
"Surgical castration is a mutilating, irreversible intervention and cannot be considered as a medical necessity in the context of the treatment of sex offenders," the committee said in a report.
"The intervention removes a person's ability to procreate and has serious physical and mental consequences."
"Moreover, given the context in which the intervention is offered, it is questionable whether consent to the option of surgical castration will always be truly free and informed," it added.
The committee said that its members found during a visit to two Czech psychiatric hospitals and two prisons in March and April 2008 that "a situation can easily arise whereby patients or prisoners acquiesce rather than consent, believing that it is the only available option to them to avoid indefinite confinement."
The Czech government, which currently holds the rotating presidency of the European Union, has largely rejected the report, arguing that its procedures conform to its own laws.