The influence of addition of Zenural 70, urea and Min-A-Zel Plus on chemical composition and quality of whole maize plant silage with different degree of compression was investigated in the paper. Experiment was two-factorial (2x3) with three replications, where factor A was a degree of compression (A₁ = 680 g/dm³; A₂ = 550 g/dm³), while factor B was an additive type (Decontrol; B₂=5 g/kg urea+2 g/kg Min-A-Zel Plus; B₃=5 g/kg Zenural 70).