This study aimed to examine the opinions of teachers and parents about the "Pre-K Mathematics Program". The case study design was used in this qualitative study. The research sample consisted of 18 parents who volunteered to participate in the study among the parents of children who attended a kindergarten affiliated to the Ministry of National Education in the Etimesgut district of Ankara in the 2019-2020 academic year and who continued their education in the classes where the "Pre-K Mathematics Program" was applied. The research sample also included three pre-school teachers who applied to the program. The sample was selected using the criterion sampling method, a purposive sampling method. The data were obtained through semi-structured interview forms for teachers and parents developed by the researchers. The data was subject to content analysis. According to both teachers and parents, our study revealed that the program increased children's mathematical concepts and skills. The participants emphasized both the positive and negative aspects of the program, and they were found to be generally satisfied with the program. The participants also drew attention to the materials in the program. The teachers found the program effective in improving educators' communication and orientation skills. They also found the program's content effective as it improved the mathematical concepts and skills, is suitable for development and is easy to apply. The teachers further commented that the materials in the program were of high quality and suitable for development. They also stated that the training method was suitable for the "show and make them do it" method. Parents' views on the most effective aspects of the program can be grouped under the themes of application and content. Based on the views of the parents, it was revealed that the children's social skills in the program increased. Based on the teachers' statements, it can be stated that the developmental difference between the children in the study and their peers was balanced with the program.