Objectives: Although urinary calcium excretion is closely related to the development of kidney stones, there was a lack of data on clinical outcomes in autosomal dominant polycystic kidney disease (ADPKD) patients. We aimed to evaluate the association between urinary calcium excretion and kidney stone, and relative factors using a multicenter prospective cohort. Methods: We obtained data from a prospective cohort with 11 centers in South Korea between May 2019 and Dec 2021. Among all subjects with ADPKD, we extracted subjects ≥18 years old with a laboratory value for urine calcium and creatinine. Spot urine calcium was divided by urine creatinine, and it was divided into the tertile range. The primary outcome was the development of a urinary stone. We additionally evaluated the relative factors associated with high excretion of urinary calcium as a urine calcium/creatinine >0.8. We used logistic regression analysis to evaluate the relative factors. Results: Among 664 patients with ADPKD, there were 63 patients who experienced kidney stones. The group with the lowest tertile of urine calcium/creatinine (uCa/Cr) significantly decreased risk for kidney stone after adjustment with age, sex, comorbidities, and laboratory variables (adjusted odds ratio [aOR] 0.416, 95% confidence interval [CI] 0.200-0.865). In addition, older age, higher serum calcium, lower phosphorus, lower uric acid, and higher blood urea nitrogen were significantly increased risk for increasing over 0.8 of uCa/Cr. Among these relative factors, serum calcium showed the most increased risk of >0.8 of uCa/Cr (aOR 3.20, 95% CI 1.61-6.35). Conclusions: We found that there was a significant association between lower excretion of urine calcium and decrease risk for kidney stones. Calcium, phosphorus, and uric acid in blood levels could be good indicators to predict higher urinary calcium excretion.