Background: Knowledge, attitude and marriage expectation are keys mechanisms in anticipating real behavior in marriage. According to the importance of marriage in Iran country this study was done with aim of study of knowledge, attitude and marriage expectation in single Tehran's Police Personal

Materials and Methods: This cross sectional study was done on 366 Tehranian single police personal in year 2014. In this study subjects selected using two-stage cluster sampling and responded to the demographical questioner and knowledge, attitude and marriage expectation questioner that validity and reliability were confirmed. In this study data were analyzed suing SPSS version 20 software and reported by independent t-test, analysis of variance with Tukey`s multiple comparison and Pearson correlation.

Results: This study consist of 366 person (172 (47%) female and 194 (53%) male -162 (44%) Line personal and 204(56%) staff personal) with mean age and work experience 26 and 5 year respectively.Among study variable job type, education, military grade, employment status, monthly income, age, year of services relationship with marriage’s expectation and military grade, income, age, ideal child size showed significant relationship with marriage’s attitude. Finally military grade, income and ideal child size showed relationship with knowledge.

Conclusion: Given the low knowledge and attitude rather marriage expectation, using practical approaches to increase these two areas and improving living condition were be suggested.