A peptide and a peptide composite according to the present invention not only show an anti-obesity effect by controlling accumulation of fat and decomposing pre-accumulated fat but also show an excellent effect with respect to diabetes by effectively reducing blood glucose. The peptide and the peptide composite according to the present invention decrease expression of PPAR, ACC, and aP2 which are lipid producing marking factors, increase expression of pHSL, AMPK-1, CGI-58, and ATGL which are fat decomposing factors, and reduce the size of fat cells and the level of blood cholesterol. Excellent activities and stability of the peptide and the peptide composite of the present invention can be very advantageously applied to medical and quasi-drug products.