Planning for Rail Transportation requires an assessment of past performance to identify and address weaknesses and gaps. Efficiency assessment is one of the tools for evaluating performance. In this study, the efficiency of Iran's Rail freight Transportation during the period April 1982-April 2022 (due to the use of the Solar Hijri calendar, the year starts in April) was evaluated using the data envelopment analysis (DEA) method, a non-parametric approach in operations research and economics. One of the policies in Iran's Rail Transportation sector in recent years has been privatization and the government's withdrawal from the management of the Rail Transportation system in order to improve performance and enhance efficiency. To examine the impact of privatization on Iran's Rail freight Transportation performance, the study time period has been divided into two distinct time periods: before privatization and after privatization. According to the results, privatization has had a positive impact on Iran's Rail freight Transportation performance and has led to improvements in efficiency in this sector. Based on the DEA-CCR model, the average efficiency score of Iran's Rail freight Transportation in the pre-privatization years was 0. 893, and after privatization, it was 0. 922. Furthermore, based on the DEA-BCC model, the average efficiency score before privatization was 0. 953, and after privatization, it was 0. 984.