For many years vlsi chip designers have been using metal-oxide semiconductor field-effect transistors (mosfets). designers have used mosfet circuits in their designs because mosfet use little power and they are cheaper to develop or fabricate. to satisfy the demands of making the chips smaller, the designers just simply shrank the dimensions to fit the circuit layouts. the shrinkage is also known as scaling. unfortunately, the continuous scaling of the circuit design will eventually cause problems within the design characteristics of a typical silicon-based transistor. these problems include short channel effect, power dissipation, leakage current, and process variation. because of the many problems that have occurred, the designers are now searching for a more efficient transistor design to satisfy the same circuit characteristics as the mosfets. engineers have been experimenting with different types of material. one of the materials is carbon-based. carbon nanotubes are described as a sheet of graphine rolled up into a cylindrical shape. this rolled up sheet of graphine can take on two characteristics depending upon the way the sheet is rolled-up. these two characteristics are metal and semiconductor in this proposed work hspice tool is used for simulation. the other tools can also used like matlab and spice3f5. here in this work first develop netlist for the mosfet based digital library. this library is compared with the cntfet based library. using cntfet model firstly develop digital library. this library design is helpful to develop netlist for complicated circuits. the results of cntfet are compared with the mosfet based digital library with 32nm bsim model. in this research work comparison analysis between both of technology made based on variation in power supply, temperature and other parameters.