Â Â Â Â The spread of religious doubt amongst people, especially students and young people in recent years has become a major concern. This study aimed to investigate the prevalence of religious doubt among students of Islamic Azad University and Yazd University. The present research is a cross-sectional survey. The population of Yazd University and Islamic Azad Yazd University students was (29630 persons) in the academic year of 2014-2015, in which 384 students by Cochran formula were selected through stratified random sampling method. A researcher-made questionnaire was used to glean the data possessing the content validity approved by the experts of the field and internal consistency utilized by the Cronbach alpha which was more than 0.7 regarding all the constructs. Data showed that the youth religious doubt regarding God's traits, Imam Mahdi and the Mahdism doctrine, woman rights in Islam and also jurisprudence were more than the average. Considering, Quran, anecdotes, Mohammad (The prophet), Imams were near average. The majority of the religious doubt was regarding the Shia branch, jurisprudence, woman's rights in Islam, and Imam Mahdi as well as Mahdism doctrine.