A method and an apparatus for estimating a parameter of a virtual screen are disclosed. The method includes determining first transformation parameters of virtual cameras relative to a reference camera of the virtual cameras based on transformation parameters of the virtual cameras relative to a physical pattern, determining second transformation parameters of the virtual cameras relative to the reference camera based on transformation parameters of the virtual cameras relative to a virtual pattern, and estimating a size parameter of a virtual screen based on the first transformation parameters and the second transformation parameters.