This study was designed to investigate the changes of phonological processes in normal Korean children aged from 2- to 6-years. Forty eight children who lived in Seoul or Kyung-Ki do were tested with a picture articulation test and their articulation errors including omissions, additions and substitutions were coded into phonological processes. Those phonological processes were discussed in several ways: syllable structure, place, manner, assimilation, tenseness, and aspiration of sounds. Data were analyzed by two ways: (1) number of subjects who showed each process and (2) percentage of occurrence of each process. Analyses in omission-addition processes demonstrated that postvocalic omission occurred most frequently, followed by velar-, alveolar-, and glottal omission. Analyses in substitution processes showed that fronting (palatal and velar), backing (alveolar), and alveolization occurred most frequently in terms of the place of sounds. In terms of assimilation, alveolar-, stopping, and aspiration assimilation occurred frequently. Analyses by the tenseness and aspiration showed similar occurrences among the 4 processes, with slightly higher occurrences in tensing and aspiration than lanxing and deaspiration. All of the processes decreased by age. The numbers of the processes showed by more than half of the children or exceeded 10％ of occurrence were 20 in 2-years of age, 10 in 3-years of age, 1 in 4-years of age, and none in ages of 5 and 6.stopping occurred most