Dendrobium officinale is a rare plant of Orchidaceae with considerable medical uses. It is also an important undergrowth plant. It can prevent many chronic diseases, such as diabetes and hypertension. In 2019, dieback disease was observed on D. officinale in China's Fujian Province. We describe the cultural characteristics and phylogeny of Fusarium equiseti in China. The pathogenicity of the isolates was confirmed using Koch's postulates. Currently, this is the first report to indicate that the causal agent of dieback disease on D. officinale is F. equiseti.