Bank Indonesia aims to achieve and maintain the stability of the rupiah value. The stability of the rupiah is the stability of the prices of goods and services, which is reflected in developments in the inflation rate. Inflation development must always be considered in determining monetary policy. This study uses the inflation data of Malang City from January 2012 to May 2019. The time-series data were analyzed using the Autoregressive Integrated Moving Average with Exogenous (ARIMAX) method. The results of the modeling show that this month's inflation is influenced by 1 to 4 months prior to this month's inflation, seasonal effects, and calendar variations before Eid al-Fitr