Oral candidiasis is caused by fungi of the genus Candida and one of the most common opportunistic fungal infections of the human oral cavity. Given the clinical variability of this disease, microbiological techniques are often required for clinical confirmation, as well as establishing a differential diagnosis with other diseases. The aim of this brief technical report is to illustrate a simple chair-side method, which can provide immediate microscopic diagnosis of this disease. We present the case of a 14-year-old boy suffering from a denture-related erythematous stomatitis, diagnosed and followed-up with a simplified direct microscopy technique. It enables an accurate diagnosis with a noninvasive and painless sampling method, linked to laboratory results.