An employee of a popular Park Slope diner was knifed in front of his workplace early today, authorities said.

The 41-year-old worker at Dizzy’s Diner on Ninth Street near Eighth Avenue was slashed in the arm, chest and back at 2:20 a.m., said cops.

The worker was rushed to Kings County Hospital and is expected to survive.

Police described the suspect as a man in his 20s. No arrests have been made in the case, and authorities aren’t sure what set off the violence.

The incident led Dizzy’s to be closed this morning.