Males are characteristically dark sooty grey above with rufous thighs and vent. In flight, the wing lining is white, contrasting with the dark wing feathers. Adult males of the closely related red-footed falcon have a dark grey wing lining. In Africa, males can be confused with melanistic Gabar goshawks, but the chestnut on the vent is distinctive. Also, there may be some superficial resemblance to the sooty falcon and the grey kestrel, but those two species both have yellow feet and cere. The wings are long as in most falcons (with a span of 63–71 cm) and at rest the wing tip reaches or extends just beyond the tail-tip.
Females can be more difficult to identify as they share a pattern common to many falcons, but are distinctive in having an orange eye-ring, a red cere and reddish orange feet. Juveniles can be confused only with those of the red-footed falcon, but lack the buffy underwing coverts.
The Amur falcon was long considered a subspecies or morph of the red-footed falcon, but it is nowadays considered a distinct species. Nonetheless, it is the red-footed falcon’s closest relative; their relationship to other falcons is more enigmatic. They appear morphologically somewhat intermediate between kestrels and hobbies and DNA sequence data has been unable to further resolve this question, mainly due to lack of comprehensive sampling.
The genus name Falco is Late Latin and derives from falx, falcis, a sickle, referencing the claws of the bird.[6] The species name amurensis is from Amurland in south-eastern Siberia.
In 2017 a payr nested in Plopu , near Danube Delta. Only one observation for Romania.