A 5-year-old boy was killed when he fell from a fifth-floor apartment balcony in Brooklyn Wednesday, cops said.

Meisels Shimon tumbled from a balcony of a building at 200 Wallabout St. in Williamsburg at about 9 p.m., according to police.

“I could see the young boy there on the floor,” said a witness, Josef Yavo. “It’s just very sad. So sad.”

An ambulance took Meisels to Brooklyn Hospital Center, where he was pronounced dead.

After the tragedy, the block of Wallabout Street teemed with ­Hasidic-community members paying their respects to the family.

It was not clear if any of the boy’s relatives were home when he tumbled.

A similar incident took place in 2014, when a 21-month-old boy died in a fall from a sixth-floor window in Crown Heights.

Theodore Levi Nemon tumbled three stories, to a third-floor balcony.

Emergency responders had to climb down from a fourth-floor balcony to reach him, but the effort was in vain.