This article introduces a new image quality assessment: QNIF (quality assessment based on noise influencing force). Considering uneven property of noise distribution, we put forward the concept of noise influencing significance area. Analyzing noise in significance area coverage is to identify the property that noise destructiveness on image structure can approach to human visual system. In addition, in view of human eyes' physiological characteristics of gaze and fast jump, QNIF also includes noise area influencing image quality. Test result shows that QNIF performance is evidently superior to traditional MSE because it can effectively estimate different types of quality reduction.