In rendering its decision, the three-member panel noted Berkowitz's commendable behavior behind bars but said it didn't outweigh the fact that the crimes he committed "displayed a cold disregard for innocent human life," the New York Post reported Friday.
Berkowitz, who has now been turned down by the parole board three times, will be eligible for parole again in two years.
He was sentenced to six life terms for killing six people and the wounding of seven others in the late 1970s. Berkowitz was dubbed the "Son of Sam" killer after he left a letter at one of the crime scenes that read, "I am a monster. I am the Son of Sam."