Basedondecadal(amountsforeachtendays)precipitationdatafrom meteorologicalstationssituatedinNorthernSouthAmericaandCaribbeanregion,adecadalprecipitationindex( DPI)wascalculatedinordertostudythe intraseasonal variability ( ISV ) of regional rainfall. The spectral analysis of DPI allows to identify signals with 20-25,30,40and50-60daysperiod.Accordingtotheanalysisoftheirspatialdistributionthesesignalsarewell definedovertheCaribbeanislandandcoastalsectorsuchasinsomesectorsoftheAndean region;the60-days signalispresented onlyover Caribbeanregion andinsomeplacesinthePacificsector;intheeasternlowlands of Orinoco and Amazon basin these signals are not clearly expressed. Exploring therelationshipbetweenregional ISV andMadden-JulianOscillationcorrelationanalysiswasmade. Due to the presence of signals different of 30-60 days, the correlation coefficients were very low. Considering