Chicken meat is one of the most popular sources of animal protein, being widely appreciated and consumed worldwide. Although the production of chicken meat has great importance in Brazil's trade balance, there are some quality aspects that need to be improved, being the tenderness the main limitation. The ultrasound technology has been proposed as an interesting technology to promote changes in the physical properties of foods. Although there are several studies associating the ultrasound technology with meat processing, the effect of this technology on chicken meat properties still needs evaluation. The objective of this study was to evaluate the effect of ultrasound technology during pre-rigor on the main quality and functionality properties of chicken breast (Pectoralis major) during refrigerated (0 a 2ºC) storage (0, 12, 24, 36 and 48 hours). Color (L *, a *, b *), pH, shear force, purge and cooking loss during storage were evaluated. The results were submitted to analysis of variance (ANOVA) and Tukey test (p < 0,05). The variation among the chicken breasts was greater than the effect of ultrasound, even conducting evaluations with the same sample. Consequently, the ultrasound technology did not exert direct positive effects to the chicken breast, especially considering the shear force. However, the interaction "Storage Time * Ultrasound Technology" caused a decrease in the pH of the samples, and then the chicken breasts became tenderness, lighter, purge and increasing the cooking loss during storage time. It demonstrated that the ultrasound technology does not directly impact the muscle fibers, but this technology can improve the chicken meat tenderness along the period of rigor mortis resolution.