"The penalty of termination is appropriate and not shocking to one's sense of fairness," schools Chancellor Joel Klein wrote of the employee, Toquir Choudhri.
In his decision last month, Administrative Law Judge John Spooner said that surfing the Web at work is equivalent to reading a newspaper or talking on the phone.
Choudhri, a 14-year veteran of the Department of Education, had been accused of ignoring supervisors who told him to stop browsing the Internet at work.
Choudhri's "abuse of the Internet at the time he is supposed to be performing his job demonstrates his disinterest in the job," Klein wrote.
Choudhri's lawyer, Martin Druyan, called the firing a "political decision."
"It's unfair, it's shocking to the conscience and it's contrary to the facts and the law," he said.