A Los Angeles man is in custody after cops say he was caught on surveillance video dropping a 7-month-old puppy down an apartment staircase.

The clip is horrifying, so watch at your own discretion -- in the video, a shirtless man cops identified as 27-year-old Joeboury Coleman is seen grabbing the dog by the collar, taking it to the stairway railing, and then callously dropping the animal.

Concerned residents at the Koreatown residence alerted the LAPD to videos posted on social media ... leading to his arrest.

Coleman pled not guilty Tuesday to 3 felony charges of animal cruelty. He is being held without bond and is due back in court on July 22 for a preliminary hearing ... according to the L.A. County District Attorney's Office.

Aside from Coleman's arrest, the other good news here is, although injured, the dog did survive. In the video, you see it running back up the stairs.

Cops say the dog was taken to a local animal shelter for treatment of a broken hind leg consistent with a fall and might need surgery.