Depends who you ask. It's one of those conditions on the border of the spectrum, that gets debated about a lot.
Certainly many autistics have NLD. In fact, among autistics with no language delay probably the majority have NLD.
But there are also people with NLD whose only autistic traits are the ones inherent to NLD. They have poor social skills, but no intense interests, no stimming, no dislike of change, strong desire to fit in, etc. I'd argue that a person like that isn't autistic. Others might argue differently - that they're not typically autistic but they are on the spectrum.
Myself, I say you need both repetitive/unusual behavior and poor social skills to be on the spectrum. Others who have one but not the other, such as OCD, gifted/talented, NLD, ADHD, etc, overlap a bit with autistics but aren't on the spectrum themselves.