The authors consider the system \[ \frac{dx}{dt} = Ax+Bu(t-h(t))+f(x,t),\tag{1} \] where \(x\in \mathbb{R}^n\), \(u\in \mathbb{R}^m\), \(A\), \(B\) are real matrices, \(a\leq h(t)\leq h_0\) is a continuous function describing uncertainties in the time delay, \(u\in \mathbb{R}^m\) is the relay control vector, and \(f(x,t)\) is continuous on \(t\) and smooth on \(x\) and presents an uncertainty in the model of the plant. Sufficient conditions for a relay delay stabilization are found. The obtained results are illustrated in the example of the relay delay stabilization for the inverted pendulum.