Multihadron events resulting from e + e - annihilation at the Υ-resonance are analysed with respect to lowest order QCD which predicts a dominant Υ decay into three vector gluons. Smearing effects due to the gluon fragmentation are so large, however, that no clear 3-jet structure or flatness is expected in the hadron final state. Instead, Monte Carlo simulations predict event structures with thrust and triplicity distributions distinctly different from those of two quark-jet and of phase space like decay mechanisms. The data are in perfect agreement with the 3-vector gluon decay as predicted by QCD and exclude dominantly phase space like or 2-quark jet decays. Also, the decay into scalar gluons is excluded by the data. An upper limit for the Υ-decay into one photon and two gluons is obtained.