Metal materials, especially titanium and its alloys, belong to a group of the most commonly used materials for producing implants. Even though they possess good mechanical and biocompatible properties, they are referred to as bioinert materials. The implantation of a titanium implant into the human body does not encourage significant biological reactions, such as the cellular processes needed for interaction between the surface of the implant and biological tissue and for stimulating the growth of tissue, known as osseointegration. Therefore, in this work, the functionalization of the titanium surface with a collagen coating was conducted. Collagen is an essential structural protein with a major role in bone construction and tissue regeneration. The functionalization with the collagen coating was carried out with the purpose of bioactivating the titanium implant surface to improve its biocompatibility, osteoconductivity, and osseointegration. Unmodified titanium samples, with a spontaneously formed oxide layer of titanium (IV) oxide, and samples modified with a collagen coating were immersed in Fusayama artificial saliva solution for 16 weeks. The bioactivity of the collagen coating was established by monitoring the spontaneous formation of calcium phosphate deposits on the sample surface after immersion. Morphology, microstructure, and chemical composition of the substrate before and after immersion into the artificial saliva solution were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and attenuated total reflectance using Fourier transform infrared spectroscopy (ATR-FTIR). The electrochemical behavior of the samples was examined using electrochemical impedance spectroscopy (EIS) in artificial saliva solution, which simulates real-life conditions of implant application.