Lyme borreliosis is a multisystem disease caused by the tick-borne spirochaete Borrelia burgdorferi. In addition to causing human illness, borreliosis has been recorded in many species of mammals, including domestic animals which come into contact with the infected tick vector. This paper describes the first two cases to the authors' knowledge of Lyme borreliosis in dogs in Belgium. Both animals suffered recurrent lameness and general prostration. In addition, one of the dogs had recurrent paralysis of nerves V, VII, IX and X, leading to dysphagia and total bilateral paralysis of the mandibular muscles. This complication of Lyme borreliosis has been well documented in human pathology, but has not previously been recorded in the veterinary literature.