The increased availability of implant-prosthetic therapy and broader indications have resulted in an increasing number of implants placed annually. This has led to a higher prevalence of peri-implant diseases. They are caused by numerous factors such as poor oral hygiene, history of periodontitis, untreated periodontitis, smoking, residual cementum, malocclusion, absence of keratinized mucosa and other iatrogenic factors. Peri-implant diseases are primarily bacterial infections developing from peri-implant biofilm. However, fungus Candida albicans is also one of the causes of peri-implant diseases. Although Candida albicans is commonly found in oral cavity of most humans, in disrupted conditions it changes its virulence and becomes pathogenic. Given that peri-implant diseases are various infections, the virulence of Candida albicans changes with the presence of primary infectious agents. Candida albicans has been proven to exist at the connection of implant to prosthetic superstructure and it has already been known that it resides in prosthetic replacements such as complete dentures. So far, the interaction of Candida albicans with other periodontal pathogens has been insufficiently researched; however, there are certain indications that its virulence changes with the presence of bacteria, but its presence is not crucial for the development of peri-implant diseases. It is important for clinicians to have thorough knowledge of the etiology, pathogenesis and microbiology of peri-implant diseases in order to make a diagnosis and administer targeted treatment.