BACKGROUND: Peste des petits ruminants (PPR) is an acute and highly contagious viral disease of small ruminants that is characterized by high fever, ocular and nasal discharge, pneumonia, necrosis, ulceration of the mucous membranes and inflammation of the gastro-intestinal tract leading to severe diarrhea. OBJECTIVES: The aim of this study was to investigate the seroprevalence of peste des petits ruminants (PPR) virus infection in sheep and cattle in Ahvaz. METHODS: Blood samples were taken from 100 cattle and 100 sheep that were kept together from different parts of Ahvaz. Blood samples were also taken from 16 vaccinated sheep   against PPR for positive control. The sera were separated by centrifuge at 3000 ×g for 10 minutes and 3 mL of serum was harvested and stored at -20 °C until determination of antibody against PPR using VN method. RESULTS: The peste des petits ruminants (PPR) antibody seroprevalence was 23% in cattle and 58% in sheep and all the sheep samples collected for control were positive for PPR antibody. CONCLUSIONS: The present study indicates serological evidence for the natural transmission of PPRV from sheep to cattle under natural conditions and provides baseline information on prevalence of PPRV antibodies in cattle and sheep population in Ahvaz.