简介：Withtheincreaseofglobalpopulation,grain-populationrelationshiphasattractedgreatattentionworldwide.InChina,grain-populationrelationshiphasbecomeanincreasinglyimportanteconomicconcern.OfcentralimportancetothefoodsecuritydebateinChinaisthegeographyofgrainsupplyanddemand.Thispaperusesagraindemandandsupplyindex(DSR)toanalyzethespatial-temporalrelationshipbetweenpopulationandgraininChinafrom1949to2007atnationalandprovincialscales.Theresultsareexaminedinthreeperiods.(1)From1949to2007,withtheincreaseofgrainproduction,therelationshipbetweenpopulationandgrainofChinaimprovedconsiderably.(2)Overthepast35years(1970-2005),onthewholethegrainproducingareashavehadgrainsurplusandcontributedtothenationbyprovidinggrain,buttheabilitytoprovidesufficientgrainisnotstable.(3)Overthepast15years(1990-2005),decreasesinplantingareabroughtpressureonnationalgrainfoodsecurity.Thepaperconcludesthatthekeytoprovidingmorefoodforthemainfoodproducingprovincesisincreasingyieldonthebasisofsteadyplantarea.