His lawyers still have five days to bring the case to the Supreme Court which, however, examines appeals only on constitutional violations.
His death sentence would become final if the nation’s highest court rejects the further appeal.
The Tokyo High Court had on March 27 rejected the lawyers’ appeal against Asahara’s death sentence. On Tuesday, it rejected an objection the lawyers filed against the decision, a court spokesperson said.
“A separate bench upheld the court’s rejection of the earlier appeal as appropriate,” she said.
The Tokyo District Court sentenced Asahara (51) to death in February 2004 for the subway attack, the murder of an anti-Aum lawyer and his family, and other crimes that claimed a total of 27 lives.
But the Tokyo High Court at that time rejected the defence’s belated document, presenting a doctor’s analysis that Asahara was faking mental illness.
Japan has been sentencing more inmates to death but carrying out fewer executions. Only one person was hanged last year and none so far this year.
Asahara, a nearly blind former acupuncturist whose real name is Chizuo Matsumoto, preached a mix of Hindu and Buddhist beliefs and predicted an apocalyptic war with the establishment.
He allegedly ordered his supporters to release Nazi-invented sarin gas on crowded trains at rush hour on March 20 1995 to pre-empt police raids on the cult. Twelve people died and thousands were injured.
He was arrested at his commune near Mount Fuji two months later.