Purpose The purpose of this study was to assess the safety and preliminary clinical results of platelet-rich plasma (PRP) injections for treating chronic plantar fasciitis. Methods Fourteen consecutive patients with chronic plantar fasciitis receiving three injections of PRP into the plantar fascia were assessed 12 months after the procedure. The modified Roles and Maudsley score and a visual analogue scale (VAS) for pain were used to evaluate the clinical results. Results According to criteria of the Roles and Maudsley score, at 12 months of follow-up, results were rated as excellent in nine (64.3 %), good in two (14.3 %), acceptable in two (14.3 %) and poor in one (7.1 %) patient. VAS for pain was significantly decreased from 7.1±1.1 before treatment to 1.9±1.5 at the last follow-up (p<0.01). Conclusions In this single-centre, uncontrolled, prospective, preliminary study, results indicate that treating chronic plantar fasciitis with PRP injections is safe and has the potential to reduce pain.