直杆蓝桉（学名：Eucalyptus maidenii）为桃金娘科桉属下的一个种。

Eucalyptus maidenii, commonly known as Maiden's Gum, is a Eucalypt species native to eastern Victoria and southeastern New South Wales, Australia. It grows in wet forest on fertile soils in valleys in subcoastal ranges.

It is a tree growing to 40 m, occasionally to 75 m, tall. The bark is white, yellow, pale orange or grey-white and smooth, shedding to ground level. The juvenile leaves are to 15 cm long and 9 cm broad, and the adult leaves to 25 cm long and 2,4 cm broad. The inflorescence is 7 flowered.