The paper investigated temporal responses of remotely sensed NDVI to precipitation and temperature during an six-year period (2000-2005) at different growing stages in desert steppe of Inner Mongolia.There were apparently positive precipitation lag effects on NDVI at different growing stages, except in July when plant was not sensitive to precipitation variations, and temperature was the primary factor limiting plant growth.No time lag between NDVI and temperature was observed in the early and late growing season.There were apparently negative temperature lag effects on NDVI in the middle growing season.