Background: Chorionic villus Sampling (CVS) has a major role in prenatal diagnosis. It is an invasive diagnostic Method in completion of primary prenatal screenings. This article is a report of our 8 years experience of CVS in Mashhad.Materials and Methods: We have done 1511 cases of invasive diagnostic procedure including 723 CVS which were included in our study and also 788 cases of amniocentesis. The gestational ages of the patients whom CVS were done for them were between 10 to 22 weeks based on the LMP. All CVS's were done by 19.5 G needles under Ultrasonographic real time guide using freehand Method by a radiologist.Results: Mean gestational age at the time of procedure was 12.5 weeks. The most common cause of CVS application was due to beta thalassemia (81%) followed by karyotype (7%), spinal muscular atrophy (werding Hoffman syndrome) (3.3%), Congenital adrenal hyperplasia (2.7%), Duchene muscular dystrophy (3%), and hemophilia, achondroplasia, paternity test, cystinuria, PKU in remaining cases. Needle insertions into placenta were done for 1 time in 517 patients (71.5%), 2 times in 163 patients (22.5%), 3 times in 38 patients (5.2%) and 4 times in 5 patients (0.7%). Any gestational complications within 1 months of CVS were considered as the complication of our procedure.As the complication of the CVS there were 13 cases of spotting without miscarriage (1.8%) and 5 cases of miscarriage (0.7%) including 3 cases of fetal death (0.4%) and one case of abortion (0.1%).Conclusion: CVS is considered as an invasive diagnostic Method in early pregnancies but it's benefits outweighing the complications in all cases that it is indicated.