This paper proposes an output-feedback control approach for sampled-data MIMO systems with nonlinear uncertainties. Design and analysis of L1 adaptive controllers are extended to sampled-data systems framework. The controller is designed for disturbance and uncertainty compensation. In this paper, a sufficient condition on the sampling time of the digital controller is obtained that ensures stability of the closed-loop system. It is shown that the proposed controller can recover the performance of a continuous-time reference system. A simulation example is provided to show the performance and robustness of the controller in the presence of measurement noise, input delay, and disturbances.