A man with at least 40 prior arrests and a history of menacing transit workers was busted Tuesday for allegedly threatening to kill two MTA employees in the Bronx, The Post has learned. 

Leonard Bethune, 46, was walking on the D train tracks at the Kingsbridge Road station around 1 a.m. when the two MTA cleaners urged him to get off track, according to a representative for their union.

“I will kill you,” Bethune allegedly snarled as he pulled out the weapon. 

The man then threatened them with a boxcutter, labor and law-enforcement sources said.

As of Tuesday afternoon, charges against Bethune were still pending, but he has about 40 prior arrests for menacing, burglary and petit larceny and past history of mental illness, according to law-enforcement sources and cops.

Bethune currently has an open menacing case in Nassau County, LI, for allegedly threatening an LIRR worker at the Garden City train station on Feb. 26, court records obtained by The Post show. 

While onboard a train there, Bethune allegedly whipped out a boxcutter and told a worker, “I will slice you” after the two got into an argument, the records state. 

He later allegedly admitted to an MTA cop that he took the boxcutter out of his pocket. 

Bethune was given a desk-appearance ticket for the incident and will be arraigned June 30 in that case, the Nassau County District Attorney’s Office said. 

Additional reporting by Desheania Andrews, Craig McCarthy and David Meyer