The two men — one of whom died of pneumonia last year — claimed their right to "private and family life" as guaranteed by the European Convention on Human Rights was being violated since they were not allowed to choose how and when they wanted to die.
In a judgment issued on Wednesday, the Court of Appeal acknowledged the current law interferes with that right but ruled the ban on euthanasia is justified. It upheld a decision by the High Court last year that any changes to the euthanasia law must be made by politicians, not judges.
In a unanimous ruling, the judges said the two men had "permanent and catastrophic physical disabilities" but said the issue of euthanasia "raises profoundly sensitive questions about the nature of our society." The judges wrote that "Parliament represents the conscience of the nation" and said the court had no jurisdiction to challenge the legal ban on euthanasia.
"I am absolutely gutted," said Paul Lamb, one of the men involved, who was severely paralyzed after a car accident.
"I was hoping for a humane and dignified end," Lamb said in a statement. "This judgment does not give me that."
Lamb said he would carry on with the legal fight for euthanasia. His lawyer said they were considering options for appealing the case to the Supreme Court, together with the widow of the other man in the case, Tony Nicklinson.
In a related case, the court ruled that an appeal by another disabled man to clarify who will be allowed to help people commit suicide, should be allowed. At the moment, the Crown Prosecution Service does not prosecute close family and friends if they help loved ones travel abroad to commit suicide as long as they act in good faith.
There is no such provision for doctors or nurses, for whom it is illegal to help or even provide medical records for patients if they suspect they may want to go abroad for assisted dying. Lawyers for a man known only as Martin argued the policy was "defective" in failing to outline cases where health care professionals might be allowed to help their patients die. Martin's family wants no involvement in his suicide.
In its ruling, the court said that while it was impossible to guarantee immunity for a health care professional who helps someone commit suicide, the current policy should be amended to be more precise.
Keir Starmer, director of public prosecutions, said it would be sensible to have the advice of the Supreme Court before any amendments are made to the guidelines. His office is appealing the decision to the Supreme Court.
In Europe, euthanasia is allowed in Belgium, the Netherlands, and Luxembourg.
Assisted suicide is usually for people who have at least some capacity to kill themselves, perhaps by drinking a lethal beverage or taking a fatal dose of drugs. It is legal in Switzerland, the only European country that allows foreigners to travel there to die.