This study aims to analyze the effect of budget participation on the performance of the government apparatus of Palu City through budgetary slack with Culture kaili “Nosarara Nosabatutu” as moderating. This research was conducted in the regional apparatus organization of the Palu City Government in 41 regional work unit. Data were analyzed using Structural Equation Modeling with WARP PLS 7.0. The results show that budget participation has a positive effect on the performance of government officials, budget participation has a negative effect on budgetary slack and negative budgetary slack on the performance of the government apparatus. The results of this study also indicate that budgetary slack was a partial mediator between the effect of budget participation on the performance of local government officials. The Kaili culture variable “Nosarara Nosabatutu” cannot be proven as a moderator.