The Method of collecting data is by Interview. The process of interview were talked to Produciton Manager and Human Resource and Development (HRD) to get Productio Factors data (Raw Materials data, Labors , and Average of Machine Working Hours). The aims of this study are to find out the influence of production factors (raw materials, labors and average of machine working hours) to the liquid fertilizer production output at PT Sidomuncul Pupuk Nusantara. The type of data which used in this study is the secondary data with the purposive sampling method. The number of samples in this study is from the time series data of each month during January 2015-December 2016 period, there are 24 samples (months). The data analysis method in this study is multiple linear regression analysis. Based on the data processing result, the quantity of raw materials (X1) influence positively and significantly to the liquid fertilizer production output in PT Sidomuncul Pupuk Nusantara and labors (X2) influence positively and not significantly to the liquid fertilizer production output in PT Sidomuncul Pupuk Nusantara, while the average of machine working hours (X3) influence negatively and not significantly to the liquid fertilizer production output in PT Sidomuncul Pupuk Nusantara. The number of return to scale (RTS) was 2,095, it means that the business condition at PT Sidomuncul Pupuk Nusantara deserve to be continue, because the value of returns to scale (RTS) is more than 1.