It spreads with rhizomes and produces a dense sod. While many stems may originate from the crown, there are no branches above ground level. The internodes of the culm are hollow. The ligule is truncate, membranous, short and abrupt. Leaf blades are flat or folded with smooth surfaces.
Groves are apparent on each side of a conspicuous midrib.
The blade terminates in a boat-shaped tip. The inflorescence of Kentucky Bluegrass is panniculate and open with a pyramid shape. Spikelets are small, flattened, and laterally compressed with persistent axes. They are not secund. Rachilla extends beyond last female fertile floret.