Loss of color during osmotic dehydration process is one of the most significant changes (Osorio et al., 2007). Physical and chemical factors responsible for loss of color during osmotic process are degradation, loss or concentration of fruit pigments and development of browning. Ames (2003) indicated that color degradation of dehydrated foods related to the browning reaction such as enzymatic or non-enzymatic browning. Therefore, the color parameters of red pitayas were measured before and after osmotic dehydration process.