This study was carried out to investigate the relationship between religiosity with parental anxiety and number of children. The population included the women of Alborz province and Tehran province (the first group included the parents with one child and the second included parents with two children and more) that among them 384 people were selected as the sample by probability (random) sampling method. The research tools were religiosity questionnaire of Khodayarifard et al. (2008) and Spielberger (1970) State-Trait Anxiety Inventory (STAI). Data were analyzed using inferential statistics of Pearson correlation. The results showed that there is no significant relationship between the number of children and maternal anxiety (R=-0.16); therefore, the results indicate the need for further attention of authorities of public health and educators to the field of religiosity and the number of children. The results also showed the role of religiosity in reducing Iranian families' anxiety.