StronggroundmotionparametersforShillongplateauofnortheasternIndiaareexamined.Empiricalrelationsareobtainedformainparametersofgroundmotionsasafunctionofearthquakemagnitude,faulttype,sourcedepth,velocitycharacterizationofmediumanddistance.Correlationbetweengroundmotionparametersandcharacteristicsofseismogeniczonesareestablished.Anewattenuationrelationforpeakgroundaccelerationisdeveloped,whichpredictshigherexpectedPGAintheregion.Parametersofstrongmotions,particularlythepredominantperiodsanddurationofvibrations,dependonthemorphologyofthestudiedarea.ThestudymeasureslowestimatesoflogarithmicwidthinShillongplateau.Theattenuationrelationestimatedforpulsewidthcriticallyindicatesincreasedpulsewidthdependenceonthelogarithmicdistancewhichaccountsforgeometricalspreadingandanelasticattenuation.