We study pluricomplex Green functions on algebraic sets. Let f be a proper
holomorphic mapping between two algebraic sets. Given a compact set K in the
range of f, we show how to estimate the pluricomplex Green functions of K
and of fβ1(K) in terms of each other, the {\L}ojasiewicz exponent of f
and the growth exponent of f. This result leads to explicit examples of
pluricomplex Green functions on algebraic sets. We also present an enhanced
version of the Bernstein-Walsh polynomial inequality specific to algebraic
sets. This article provides a theoretical framework for future investigations
of the rate of polynomial approximation of holomorphic functions on algebraic
sets in the style of Bernstein-Walsh-Siciak theorem