This paper presents a recursive solution of an estimation strategy that incorporates non-uniform measurements for a Linear Time-Invariant (LTI) Systems. The estimator is based on a modied Receding Horizon Estimator. The proposed approach allows to recursively estimate the system state, reducing the estimation error, by including measurements available at different sampled time using a well-known structure. A discussion of observability of the system in the presence of non-uniform measurements and the convergence conditions of the proposed estimator are also presented. Finally, numerical simulation shows the effectiveness of the proposed estimator in comparison with a Kalman lter with augmented state method.