The aim of this work was to study prospective process validation of Amoxicillin trihydrate and Potassium clavulanate oral suspension. Three initial process validation batches of same size, method, equipment and validation criteria were taken. The critical parameters involved in sifting, mixing and filling were identified and evaluated as per validation master plan. Uniformity of mixing is optimum in 30 minutes as standard deviation is between ±0.29 to ±0.30. Drying time of 240 min is suitable for obtaining moisture content within 0.4 -0.6 %. The drug content of reconstituted liquid suspension on day 1 and day 7 were within the limits of 90 % to 120 %. The outcome indicated that data obtained by process validation of three batches provides high degree of assurance that manufacturing process of Amoxicillin trihydrate and Potassium clavulanate oral suspension produces product meeting its predetermined specifications and quality attributes.