Abstract: In the course of measuring data processing, the distribution and quality of the surveying data can be approximately described by the histogram. But in the course of drawing histograms, the unusual histograms, e.g. bimodal histogram are often presented. For such unusual situation, people impute to the measuring data itself. Analyzing the measuring data which draws the unusual histogram, this paper discusses the question that the histogram block melts histogram, and provides the formula of calculating the fuzzy frequency and method for drawing the fuzzy histogram. The superiority of the fuzzy histogram is stated.