Introduction: Preeclampsia is a major cause of maternal and perinatal morbidity, and mortality. Early detection and prompt treatment will ameliorate the effect of preeclampsia, its complications and improve maternal and perinatal outcome. Aims: To determine the role of spot urinary calcium to creatinine ratio to predict preeclampsia in asymptomatic pregnant women in Lagos Island Maternity Hospital. Research Methods: The study was a prospective cohort study involving 127 normotensive pregnant women with spot urinary calcium creatinine ratio of ≤0.04 at gestational ages of 20- 24weeks in the study group and equal number of pregnant women (matched for age, parity and body mass index) with spot urinary calcium creatinine ratio >0.04 as the control. The two groups were studied for the development of preeclampsia and correlation made in reference to their spot urinary calcium creatinine ratio samples taken at recruitment. The results were analyzed by Chi square test and logistic regression test to find the significant association of findings of preeclampsia and urinary calcium-creatinine Ratio. P- value of <0.05 was considered statistically significant at a confidence interval of 95%.