Background: The chronic kidney disease-associated pruritus is very common and its impact on patient's quality of life is relevant. Although pathophysiology is not clear; it seems that phosphorus values influence the intensity of itching. The objective of the current study is to find the correlation between phosphorus and the Worst Itching Intensity Numerical Rating Scales. Methods: Cross-sectional study that included subjects with Diabetes and Chronic Kidney Disease who had serum phosphorus measured and performed the WI-NRS. To find the correlation between these variables, the Spearman Correlation Coefficient and the Concordance Correlation Coefficient were used. The analysis was performed using STATA 14.0. Results: A discrete direct association was found between phosphorus and WI-NRS (rs = 0.445, p = 0.013). The concordance analysis was not relevant. Conclusion: The present study cannot suggest an association between serum phosphorus and WI-NRS.