The aim of the present study was to test the reliability of theory of mind task performance by individuals with a learning disability. Across a series of three false belief tasks and two belief-desire reasoning tasks reliability was moderate–although it was no lower than has been found over a period of 3 weeks in normally developing children. The overall level of performance on the tasks was also only moderate, with approximately half the subjects passing on any one false belief task, and one quarter on any one belief-desire reasoning task. Reliable passers had higher VMA and NVMA than unreliable passers and subjects who failed. Given the important interpretations made regarding the representational skills of individuals on the basis of their responses in such experimental tasks, further work investigating the psychometric properties of the tasks is required with both typically and atypically developing individuals.