Recent research findings have consistently highlighted significant developmental benefits of early animal-child interactions such as promotion of empathy and social skills and the need for effectively informing and sensitizing different age groups towards animals. Despite these well-documented advantages, there is a lack of validated instruments specifically designed to assess preschoolers' attitudes toward animals, a gap that hinders the development of evidence-based and age-appropriate educational interventions. The present study addressed this gap by constructing and validating the Scale of Preschoolers' Attitudes toward Companion Animals (SPACA). The participants were 1,081 preschool children (age range 3.92-5.83 years) from public and private schools who participated in the educational program EY ZOON: Learning to live with animals - Actions to raise awareness of children, parents and teachers towards companion animals. The final version of the SPACA comprised 19 categorical items and revealed a coherent three-factor structure: (a) caring for and from animals, (b) cruelty and stereotypes against animals, and (c) adults' involvement. The factor analysis demonstrated acceptable psychometric properties, supporting the scale's reliability and validity. Findings underscore the importance of employing standardized and psychometrically sound tools to capture young children's awareness and sensitivity toward companion animals from the earliest years of life. Such tools not only enable the systematic assessment of preschoolers' perceptions but also provide a crucial foundation for the design, implementation, and evaluation of targeted educational programs that foster empathy, responsibility, and animal welfare values at a formative stage of development. This work represents an original contribution to the field, offering the first validated scale specifically tailored to preschoolers' attitudes toward animals.