The relationship between altitude and yield of Castanea mollissima in mountainous area of Northeast Fujian was studied by randomized block design in this experiment.According to the comparative analysis, the result showed that there was significant difference in the fruit buds number and the field of Castanea mollissima among different altitude, but there was not proportion relation between altitude and yield of Castanea mollissima.The suitable altitude for planting Castanea mollissima was 400~800 m, which could bring high yield and good economic benefit.