This paper presents a longitudinal study on manufacturing strategy clusters in two time periods with a six-year interval. In longitudinal study, data were collected from a representative sample in different times. To conduct a longitudinal study, two different types of clustering on the manufacturing strategies were used in factories of Iran in two time periods. For this purpose, the data of production factories at two time periods (years between 2009 and 2015) were used. Clustering validation was studied by using discriminate analysis, and then changes created in production targets of these clusters have been examined by using Euclidean distance, Multivariate Analysis of Variance and Variance Analysis. The results show that there are similarities and differences between clusters in two time periods.