Pregnancy is a physiological condition that affects a woman's life, including susceptibility to oral disease. Increased levels of female hormones impact the growth of periodontal pathogenic bacteria. In several mutants, Streptococci levels are said to be greater during Pregnancy. Thus, the cariogenic bacteria predominating in plaque and saliva will develop more acids through fermentation, leading to dental caries. The present study aimed to assess (Decay and Decayed, Missing and Filled Surface) value and mutans streptococci counts in pregnant and non-pregnant women. The method was applied to 80 women, with an age range of 20 to 30 years. The study group comprised 60 pregnant women divided into three equal trimester groups (20 pregnant women in each trimester), while the control group consisted of 20 married non-pregnant. The salivary samples were collected under standardized conditions for microbiological analysis and oral examination done by caries experience (Decay and Decayed, Missing and Filled Surfaces). Results revealed that Decayed, Missing and Filled Surfaces value and mutans Streptococci count was higher in (study groups) in comparison to (control group) in addition to the correlation between the viable count of mutans streptococci (CFU×105 /ml) and DMF appeared positive significant result in this study. Keywords: Pregnant women, DMFs, mutans streptococci.