Prostatitis is a clinical condition of difficult management and with limited antimicrobial options, especially in the setting of antimicrobial resistance. Recurrences are frequent and can be severe. Limited reports support the use of fosfomycin for chronic prostatitis by ESBL-producing bacteria. We reported a case of a patient with chronic prostatitis caused by ESBL-producing Escherischia coli with several relapses after prolonged periods of treatment with broad-spectrum intravenous antibiotic therapy and with recurring urinary symptoms after transuretheral prostatic resection. After resolution of the last infection, we performed a long-term eradication antimicrobial treatment with 3 g of fosfomycin once daily, altered to 3 g every 48 h after 10 days due to diarrhea (which resolved with the dose change). After three months with this dosage, fosfomycin was switched to a once-weekly regimen which was maintained for further 9 months. After 9 months of follow-up without antimicrobial treatment, the patient has remained free of urinary symptoms. Experience with fosfomycin for chronic prostatitis caused by ESBL-producing E. coli is limited to three case reports and two case series. Intraprostatic measurements have shown adequate penetration of fosfomycin into prostatic tissue. Accordingly, our report suggests that fosfomycin can be used as eradication therapy in a patient with a prior history of chronic prostatitis by ESBL-producing bacteria with recurring urinary infections after surgical treatment.