Few instruments have been suitably translated and validated for measuring motivational aspects linked to reading in the Spanish-speaking world. The present study was aimed at psychometrically validating the Gambrell, Palmer, Codling, and Mazzoni's Motivation to Read Survey (MTS; 1996), which comprises 2 subscales: reader's self-concept and value of reading. A convenience sampling process was used to recruit 698 Chilean 3rd, 4th, and 5th graders attending 4 subsidized and private schools in the Metropolitan Region of Chile; 53% of them were boys and 47% were girls. The scale was translated using the back translation method. Internal consistency (Cronbach's alpha), expert rater, and construct validity analyses were performed using exploratory and confirmatory factor analysis. Results show that the Spanish version of the MTS is a reliable and valid instrument that can be used for research and instructional purposes, allowing researchers and teachers to delve deeper into reading motivation in Spanish-speaking children.