Prepared by the deposition of a solid electrode and electrolyte, all-solid-state batteries are a promising next generation battery system. Aerosol deposition (AD) offers many advantages compared to the conventional thin film deposition methods, including the deposition of a crystallized thin film with no heat treatment and a fast deposition rate. In this study, a LiFePO4/C composite thin film is directly fabricated using a LiFePO4/C composite raw powder. SEM and EDS results show the successful deposition of a LiFePO4/C composite thin film on a stainless steel substrate and X-ray diffraction patterns reveal that the as-deposited thin film has a crystalline structure, corresponding to the olivine phase, without any heat treatment. In a CV test, oxidation and reduction peaks appear at 3.51 and 3.36 V, corresponding closely to the peaks of bulk olivine LiFePO4. Furthermore, the profiles of the charge and discharge curves are similar to those of the bulk electrode and the discharge capacity is 31.1 μAh cm−2 μm−1 in the first cycle. After 20 cycles of 10.65 and 106.5 μA cm−2 μm−1, the capacity is recovered to 30.7 μAh cm−2 μm−1. Aerosol deposition can potentially be used in the fabrication of all-solid-state batteries.