Are human beings related to reptiles?

Ultimately all organisms are related. Humans are mammals, which are not closely related to reptiles. Mammals and reptiles belong to a group of animals called amniotes, which they also share with birds. Amniotes include all land vertebrates except amphibians. The last common ancestor of mammals and reptiles lived over 300 million years ago in the Carboniferous period. Shortly after the first amniotes branched off from amphibians they split into synapsids, which became the ancestors of mammals, and sauropsids, which became the ancestors of birds and all modern reptiles.