The lambdoid suture, or lambdoidal suture, is a dense, fibrous connective tissue joint on the posterior aspect of the skull that connects the parietal bones with the occipital bone.

If certain bones of the skull grow too fast, then craniosynostosis (premature closure of the sutures) may occur.

If the lambdoid suture closes too soon on one side, the skull will appear twisted and asymmetrical, a condition called "plagiocephaly".

[citation needed] The lambdoid suture can be damaged by a fall backward.

[2] The lambdoid suture is named due to its uppercase lambda-like shape.