The comprehension of the place value concept which is based on the grouping of numbers in accordance with distinct systems is not so easy. One of the sources that may contribute to the comprehension of the place value and making connections with daily life is children's books. The effects of several tools on the comprehension of the place value have been analyzed in the literature, but the effects of children's books in this regard have not been so frequent. Therefore, the aim of the study is to analyze the effects of the fifth-grade mathematics lessons integrated with children's books on the students' place value understanding. The study was designed through the case study which is a kind of the qualitative research methods. The participants of the study are 32 fifth grade students. The data of the study were obtained through the place value test, the place value achievement test, and an interview form. The findings indicate that the mathematics lessons integrated with the picture books have positive effects on the fifth-grade students' comprehension and achievement about the place value. Also, the students participated in the study mostly reported positive views about the mathematics lessons integrated with the children's books.