Abstract: Objective To study the influence factors for encrustation of double J stent in patients with urolithiasis. Methods In this study, there were 84 urolithiasis patients with double J stent included from February to July 2014 in our hospital. The encrustation on double J stent was evaluated by a PC stereo microscope. The interrelated clinical data were obtained, then the factors which may affect the encrustation were studied by logistic regression analysis. Results The mean indwelling time was （17.0±6.0） d, and a thin encrustation formed on the stents for most cases 〔67/84（79.8%）〕. Compared with the cases who did not form a thin encrustation, those having a thin encrustation formation on the stent were younger 〔（44.9±11.5） vs. （54.4±12.6），P=0.004〕. The patients with proteinuria got a higher rate of encrustation 〔62/73（84.9%） vs. 5/11 （45.5%），P=0.002〕.The patients with urinary tract infection had a higher rate of encrustation 〔26/28（92.9%） vs. 41/56（73.2%）, P=0.035〕. The patients with hematuriaalso got a higher rate of encrustation 〔67/80（83.8%） vs. 0/4，P=0.001〕。Different sex, retention time,serum calcium,inorganic phosphorus,uric acid,urine pH,lithiasis component had no effects on encrustation (P>0.05). Logistic regression analysis showed that age and proteinuria was retained as independent correlated factors with encrustation (P<0.05), while hematuria and urinary tract infections had a low intensity correlation with encrustation (P>0.05). Conclusion For encrustation of double J stentin patients with urolithiasis, younger age, increased urinary protein, hematuria and infections are important risk factors.