In the period between October 1st and November 30th, 2006, we investigated a total of 3188 episodes of UTI (802 among males; 2386 among females) recorded in 108 family medicine offices in 20 cities in Croatia. The most common UTIs in women were acute uncomplicated cystitis (62%), complicated UTIs - cystitis and pyelonephritis (14%), urethritis (9%), acute uncomplicated pyelonephritis (6%), recurrent cystitis (5%), asymptomatic bacteriuria (3%) and recurrent pyelonephritis. The most common UTIs in men were complicated UTIs - cystitis and pyelonephritis (48%), urethritis (25%), prostatitis (24%) and asymptomatic bacteriuria (3%). Etiological diagnosis was made in 999 (31%) UTI episodes before antimicrobial therapy was given. The most frequently isolated causative pathogens were Escherichia coli (77%), Enterococcus faecalis (9%), Proteus mirabilis (5%), Klebsiella spp (3%), Streptococcus agalactiae (3%) and Enterobacter (1%). Antimicrobial drug was administered in 2939 (92.19%) UTI episodes, in 1940 (66.01%) as empirical therapy, and in 999 (34%) as targeted antimicrobial therapy. The most commonly administered drug in empirical therapy for acute uncomplicated cystitis, recurrent cystitis and urethritis in women was cephalexin, for acute uncomplicated pyelonephritis and complicated UTIs in women co-amoxiclav, and for UTIs in males ciprofloxacin. The results of this research of 3188 UTI episodes in family medicine physicians' offices provide a confirmatory answer to question whether empirical antimicrobial therapy of UTI prescribed by Croatian family practitioners is in accordance with the national guidelines.