We discuss $Z$-production in deep inelastic scattering $e + p → e + Z + X$ using the parton model, in the context of the Standard Model at leading order. In contrast to the deep inelastic $ep$-scattering ($e+ p → e+ X$), where ($\tilde Q^2$) the momentum transfer square, is unambiguous, in the case of boson production it depends upon the mechanism involved, that is, it is related to the electroweak interactions. We present estimates for the total cross-section as a function of
$\sqrt{s}$, the energy of the $ep$ system, in the range $300 ≤ \sqrt{s} ≤ 1300$ GeV, and also for different assignements of ($\tilde Q^2$).
