In this paper, a series of laboratory tests on shrinkage of plaster materials are presented. The plaster materials consist of cohesive soil, sand and different natural fibres. Three types of fibres, wheat straw, barley straw and wood shavings, were used as reinforcement in the tests. The shrinkage behaviour of earth plasters was studied by laboratory tests for different compositions and under different curing conditions. The specimens of plaster material were dried under a constant temperature of 30, 50 and 70°C, respectively. The effect of the following factors on shrinkage was investigated: temperature, soil composition, fibre type and fibre content. It was established that shrinkage crack formation decreases with increasing fibre content and increases with increasing soil content. In general, it was also found that lower curing temperature and higher fibre content are to be preferred to improve the performance of earth plasters.