Recently, the first Cretaceous velvet water bug (Heteroptera: Hebridae), Archaeohebrus alius Zhang, Ren & Yao 2024, was described from Myanmar amber, based on one male specimen. In the present contribution, we report the finding of the first female of this species, based on one specimen collected in the same area. The amber piece containing the studied fossil originated from Noije Bum, near Tanai Village Hukawng Valley, Kachin State, northern Myanmar. It is dated as the earliest Cenomanian, mid-Cretaceous (98.79 ± 0.62 Ma). The female studied has an elongated body (2.28 times longer than wide) with a subtriangular head and hexagonal pronotum. The hemelytra are fully developed, bearing three closed cells and almost reaching the end of the abdomen. Finally the external genitalia has an eightht abdominal segment strongly concave towards the middle; the ninth abdominal segment is elongated and looks subtrapezoidal in lateral view; the first valvifer is well developed and has an isosceles triangle shape in lateral view; the three valvula are visible and well developed, subrectangular in lateral view; and the ovipositor is well esclerotized and resting inside the valves. In general, the female looks similar to the male, but is a little more slender, with the head and pronotum more stylized. This dimorphism has been observed in other modern Hebridae. In addition to the diagnostic characters shared with the male, the genitalia details observed in the female support the placement of this species in Hebridae.