The ratio of the number of $W+1$ jet to $W+0$ jet events is measured with the D0 detector using data from the 1992--93 Tevatron Collider run. For the $W\ensuremath{\rightarrow}e\ensuremath{\nu}$ channel with a minimum jet ${E}_{T}$ cutoff of 25 GeV, the experimental ratio is $0.065\ifmmode\pm\else\textpm\fi{}0.003\left(\mathrm{stat}\right)\ifmmode\pm\else\textpm\fi{}0.007\left(\mathrm{syst}\right)$. Next-to-leading order QCD predictions for various parton distributions agree well with each other and are all over 1 standard deviation below the measurement. Varying the strong coupling constant ${\ensuremath{\alpha}}_{s}$ in both the parton distributions and the partonic cross sections simultaneously does not remove this discrepancy.