Calamaria buchi, also known commonly as Buch's reed snake and the Dalat dwarf snake, is a species of snake in the subfamily Calamariinae of the family Colubridae. The species is endemic to Vietnam.
The specific name, buchi, is in honor of French missionary Father Buch who collected the holotype.
The diameter of the eye of Calamaria buchi is equal to the distance from the eye to the mouth. The frontal is twice as wide as a supraocular. There is a preocular present. There are four upper labials, the second and third contacting the eye. The holotype, a female, has 221 ventrals.
Calamaria buchi is found in Lam Dong Province and Ha Tinh Province, Vietnam.
The preferred natural habitat of Calamaria buchi is forest, at elevations from sea level to .
Calamaria buchi is terrestrial, fossorial, and nocturnal.
Calamaria buchi is oviparous.