Ganji, 46, an outspoken critic of the state's clerical leadership, was jailed in 2001. He was taken to hospital last Sunday after a five-week hunger strike.
His wife said on Friday his health was deteriorating.
"I call on the judiciary and human rights groups to pay serious attention to my client's dangerous situation," Ebadi said in a statement.
"Ganji's wife says his hunger strike continues in the hospital. He has even lost weight since being hospitalised."
Ebadi also criticised Iran's judiciary for refusing to allow her to visit him.
"As Ganji's lawyer I have not been allowed to visit him in the hospital," said Ebadi. "This is unlawful."
There was no immediate official response to the statement.
Outgoing President Khatami (R)
has called for Ganji's parole
Ganji's family and rights activists say he has lost more than 23kg during his 43-day hunger strike, which he says is a protest against his continued detention while suffering chronic asthma and back pain.
Senior judiciary officials have denied the investigative journalist is on hunger strike and said his admission to hospital last weekend was for knee surgery.
Pardon being considered
Ganji, a former Revolutionary Guard turned radical reformer, was sentenced to six years in prison after a series of articles he wrote linked officials to the murder of political dissidents.
The European Union and the United States have both called for his release.
Iran's outgoing President Mohammad Khatami has urged that Ganji be paroled since he has just six months of his sentence left to complete.
Iran's judiciary has said it will not yield to international pressure to free Ganji, but a senior judiciary official said on Thursday that a pardon might be considered.
Tehran has a dismal record on press freedom, closing more than 100 liberal publications and jailing several journalists in a concerted crackdown on reformist media since 2000.