The horror fiction writer made the revelation by posting on the micro-blogging site.
"Trump has blocked me from reading his tweets. I may have to kill myself," he wrote.
"Blocked! Condemned to an existential wasteland of Trumplessness!" his another post read.
Soon after "The Way Station" author tweeted, "Harry Potter" writer J K Rowling said she had King's back.
"I still have access. I'll DM them to you," Rowling wrote.
King was blocked after he posted about his daughter Ivanka.