Focusing on the issues of low efficiency, being easy to be influenced by subjective factors and deviation of the evaluation results caused by the traditional edge quality evaluation which relies on experts, a new mapping evaluation operator called Geographical Mapping Operator (GMO) was proposed. Fuzzy comprehensive evaluation was applied to the edge quality evaluation, and the comment rate and evaluation index were determined according to the national standard, as well as the fuzzy weight vectors of evaluation factors were determined through the entropy weight method. Besides, the new operator was proved by theory. When applying the GMO to the actual data, the unqualified quality of earth data accounts for 65% before edging, but the perfect quality of earth data accounts for 55% after edging, which indicates the effectiveness of GMO.