卫星DNA由串联排列、不断重复的非编码DNA组成，它是着丝粒的主要组成部分，也是异染色质的主要结构部分。

卫星DNA与小卫星和微卫星DNA一起被称为串联重复。

一些人体内的卫星DNA类型包括：

Satellite DNA consists of very large arrays of tandemly repeating, non-coding DNA. Satellite DNA is the main component of functional centromeres, and form the main structural constituent of heterochromatin.

The name "satellite DNA" refers to how repetitions of a short DNA sequence tend to produce a different frequency of the nucleotides adenine, cytosine, guanine and thymine, and thus have a different density from bulk DNA - such that they form a second or 'satellite' band when genomic DNA is separated on a density gradient.