Recently, lead-free piezoelectric thin films have received increasing attention due to the growing demands for mircoelectromechanical systems and the significant progress in lead-free piezoelectric research. Here, potassium sodium niobate [(K, Na)NbO3 (KNN)]-based thin films were fabricated via a sol-gel method. The effects of pyrolysis temperature on the resulting microstructure and electrical properties of KNN-based films were investigated. The KNN-based film pyrolyzed at 550 degrees C and annealed at 700 degrees C shows a dominant (100) orientation with a high texturing degree of 91.7%. The microstructures, morphologies, piezo- and ferroelectric properties of the KNN-based films were discussed in association with different pyrolysis temperatures. The crystallization mechanism of the (100) textured KNN-based thin films was elaborated in detail.