The main objective of this survey was to know young adults’ perceptions and use of public libraries in Sabzevar, Iran. Research population included students aged 12 to 15 who were public library members and were using public library services several times in a year. According to Cochran sampling size formula, the sample size was calculated 180 persons that were chosen by random cluster sampling technique. Required data was gathered by a researcher made questionnaire and analyzed by descriptive and inferential statistics using SPSS 20. The findings showed that the necessity of public library use was more than moderate extent from the young adults’ perspective. The use of loan services, reference services, and information services was more than moderate extent, while use of extension services was less than moderate extent. The main reason for public library use was use of library non-text books and educational aid books, and the main obstacle to use public library was huge amount of home work and lack of time. Further, there was a direct significant relationship between the use of public library services and socioeconomic and cultural status.