Enterprise Resource Planning Systems and Integrated Financial Management Information System have such an important role in global success and become more complex overtime. ERP and IFMIS have not been addressed in full, their challenges such as legacy systems as the main assets in operations and performance are strongly wanting. Unlike the ERP, Literature on IFMIS is very scanty and hence not exhaustive. This Research attempts to utilize Sample size of 300,adopted from thesis on Public sector .The Research employed Analysis of Moment Structures (AMOS) for modeling to compare Models A and B to test the systems, GFI was utilized to determine model goodness of fit, Comparisons of Path diagrams was used to examine the error difference, Multiple Group Model Comparisons and the Latent growth model curve was used to establish the extent to which the systems performs in Public Sector within various departs. Finding indicate that the two models of ERP and IFMIS differ, it was clear that equal Standardized Regression weight model results were substantially worse on overall model fit , specifically on IFMIS. The results further yielded an error difference of 10% on the IFMIS while an error difference of 1 % on ERP indicating that ERP can be more reliable in public sector in terms of efficient and accurate than IFMIS. Results obtained rejected the equal Standardized Regression Weight for IFMIS Model–B in favor of the ERP Model–A . A latent growth curve model indicated that the IFMIS use varied, indicating a significant individual variability in the initial level. On rate of change it indicated an uptrend which was progressive. A comparative analysis identified issues on ERP which proved to be crucial for its application as a proper system use in Public sector, however some limitations in terms of: Error difference, Low model goodness of fit were faced by the IFMIS .This research recommends that the administration should ensure the information generated by IFMIS is consistent, timely and adequate.