A capacitor with nanotubes and a method for fabricating the same are provided. The capacitor includes: a lower electrode including a patterned conductive layer and a plurality of nanotubes formed on the patterned conductive layer in the shape of whiskers without using a catalytic layer; a dielectric layer formed on the lower electrode; and an upper electrode formed on the dielectric layer. The method includes the steps of: forming a conductive layer for forming a lower electrode; forming a nanotube array including a plurality of nanotubes formed on the conductive layer without using a catalytic layer; forming a dielectric layer on the nanotube array; and forming an upper electrode on the dielectric layer.