Introduction: Provision of substructure facilities and technology with new interaction between patient and physician - to get medical and health information – increased the usage of Internet while there is no control on the quality of delivered information by websites in health and medicine field that affects human life , is very important. One way for reliability of information quality is consider some criteria, such as Silberg criteria. 

Methods:This is a survey research , 75 persian medical and health websites were surveyed by silberg criteria .These websites content search in two search engine yahoo, google and website of healh and medical education ministry and some of Persian subject directory like linkestan , link , hotlink. Then silberg criteria check list for these websites were filled with direct observation. Then collected data analyzed in spss statistical software.

Results: Results showed that half of websites introduced their references. (first principle in silberg base) , about 67% of websites introduced their authors (second principle in silberg) while , only 16% of websites have no responsibility for published information in their websites , and only 20 percent of websites mentioned date of website establishment. Scores that gained from Silberg criteria were between 0-8 from total score 9 and any of websites don't get total score.

Conclusion: This research showed undesirable quality of presented information in Persian medical and health websites. As a result a Persian user who wants to use Internet as a information resource should get a consultation with specialists and also search with complete intelligence.