In this paper, we propose naturalness-preserved tone mapping in images based on perceptual quantization (PQ). PQ is a transfer function based on Barten's contrast sensitive function (CSF) which represents human visual perception on luminance, and we adopt it to generate a limit curve for perceptual contrast enhancement. First, we obtain a limit curve in an image based on PQ transfer function to adjust the degree of contrast enhancement. Second, we redistribute the histogram using the limit curve and achieve perceptual contrast enhancement. Experimental results demonstrate that the proposed method effectively enhances contrast in images while successfully preserving naturalness.