Abstract: The routine nutritive components and gross energy contained in samples of Pennisetum purpureum.gathered from east suburban area of Kunming City in the four seasons were determined.The results showed that there were differences in the nutrition and energy contents among the sample collected in different seasons.The contents of routine nutritive components in the samples gathered in the spring were as follows:11.52% of crude protein,4.14% of ether extract,27.06% of crude fiber,14.23% of ash,43.05% of N free extract,and 16719 J/g of gross energy.The contents of routine nutritive components in the samples gathered in the summer were as follows:9.76% of crude protein,3.23% of ether extract,30.07% of crude fiber,10.15% of ash,46.79% of N free extract,and 16735 J/g of gross energy.The contents of routine nutritive components in the samples gathered in the autumn were as follows:10.66% of crude protein,3.08% of ether extract,30.01 % of crude fiber,10.63% of ash,45.62% of N free extract,and 16402 J/g of gross energy.The contents of routine nutritive components in the samples gathered in the winter were as follows:7.13%of crude protein,1.11% of ether extract,40.55% of crude fiber,9.04% of ash,35.44% of N free extract,and 17238 J/g of gross energy.Furthermore,the determination showed that there were also differences in contents of nutritive components between the samples simultaneously gathered from Kunming and Chongqing.