A production method for a semiconductor integrated circuit includes: creating a model parameter of an element constituting a cell, wherein the model parameter is defined by a design value and a distribution function of variability from the design value; performing a circuit simulation using the model parameter to create a response function that expresses response of cell characteristic to the model parameter; and creating a statistical cell library by using the response function. The statistical cell library used for circuit design and verification gives an expected value and statistical variation of the cell characteristic. The statistical variation is expressed by a product of the distribution function and sensitivity. The sensitivity is calculated based on the response function. When the model parameter is updated, the statistical cell library is updated by using the post-update model parameter and the response function without performing a circuit simulation.