This study describes an experiment for image quality evaluation on a new OLED TV under high dynamic range (HDR) and wide colour gamut (WCG) condition. Eight attributes including peak brightness, blackness, colourfulness, contrast, reality, sharpness, texture details and overall image quality, were investigated. The results were used to understand the relationship between image quality and those attributes. An image quality model for OLED TV was derived using principle component analysis method. The model includes three main factors, spatial and colour quality, black level and brightness.