Objective: This study aimed to review results of urinalysis with flow cytometry technique at the time of diagnosis of urinary tact infection (UTI), and to determine uropathogenes with their antibiotic resistance patterns in children with first-time UTI. Material and methods: This single-centered, retrospective, cross-sectional study was conducted from January 2015 to December 2017. The study included 361 children with a first-time UTI diagnosis. Age, gender, results of automated urinalysis, urine culture results were recorded. Results: Mean ages of children were 55.8±50.7 months. E. coli was the most common isolated microorganism followed by K. pneumoniae, Proteus, Enterococcus, and P. aeroginosa. Median count of pyuria was 44 leukocyte/mm3 (range:0-2954/mm3 ). Median count of pyuria in female and male patients were 53 and 22 leukocyte/mm3 , respectively (p=0047). A total of 98 patients (27.1%) had no pyuria. Proportion of pyuria in female and male patients were 81.2% and 76%, respectively (p>0.05). Mean age of patients with and without pyuria were 59±52 months and 46±44months, respectively (p<0.05). According to uropathogen, there was pyuria at the ratio of 60% in Pseudomonas, 62.5% in Enterococcus spp, 66.7% in Proteus, 78.3% in Klebsiella, and 82.7% in E. coli. Children with UTI induced by E. coli had resistance ratios of 30.5% and 22.4% to cefixime and ceftiaxone, respectively. Children with UTI by Klebsiella spp had resistance ratios of 47.8% and 39.1% to cefixime and ceftriaxone, respectively. Conclusion: E. coli was the most common uropathogen in children with first-time UTI. Pyuria may be lacking according to age, gender, and type of uropathogene. Pyuria level was higher in females. In addition, ceftriaxone and cefixime resistance is increasing making ampirical treatment choices limited.