Infrared drying ultrasound pretreatment uses lower temperatures than conventional methods of drying, which are based on the use of thermal energy with a large water loss, keeping the colour, texture and structure. The aim of this work is to investigate the impact of high-intensity ultrasound of different amplitudes on drying the pieces of apple, as well on their colour and texture. Ultrasound device working at a frequency of 24 kHz with a power capacity about 200 W was used for ultrasound pretreatment. The amplitudes used are 0%, 20%, 40%, 60%, 80% i 100%. Optimizing the drying process using mathematical modelling of temperature and moisture distribution in the material can reduce energy consumption in a infrared dryer. The results show that the use of different amplitudes of ultrasound reduces the time of drying and increases water diffusivity due to the formation of microscopic channels in apple structure. Hardness of samples gradually drops with increase of intensity and duration of ultrasonic treatment, while elasticity of samples increases with high intensity.