A study was conducted to compare and evaluate the three prominent simulation languages; GPSS/H, SLAM, and SIMSCRIPT II.5. The main objective of the research was to identify the most appropriate language among the three as applied to manufacturing facility simulation. The most important qualitative features of the three languages were discussed and compared based on a pre-defined set of criteria. The performances of the three languages were evaluated based on another set of criteria. A hypothetical model of a manufacturing facility was used for the evaluation. An experiment was designed to measure the performances of the languages under different conditions. Three model configurations and five different simulation periods were considered in the design of the experiment. Intensive statistical analyses were conducted to analyze the results that were collected from the various trials of the simulation models;In all the cases that were considered in the experiment, GPSS was found to be the most appropriate language among the three. In comparison of period lengths and scale of model, it compiled and executed faster, it used less CPU and memory time, and the rates of change in execution, CPU, and memory times variables were much less than those of the other two languages due to increases in the simulation period and to enlargements in the model size.