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Calibrations were performed for three types of neutron ambient dose equivalent rate meters, i.e., Aloka TPS-451C (Hitachi), KSAR1U.06 (Baltic Scientific Instruments), and Model 12-4 (Ludlum), using a standard field of a 241Am–Be source. The measured total neutron ambient dose equivalent rates, H*(10)＇tot, were analyzed to obtain the direct neutron ambient dose equivalent rates, H*(10)＇dir, using the ISO 8529-2-recommended general-ized-fit method, semiempirical fit method, and reduced-fitting method (RFM) fit methods. The calibration factor (CF), defined as the ratio between the conventional true value of the neutron ambient dose equivalent rates in a free field, H*(10)＇FF, and H*(10)＇dir, was evaluated as one of the important characteristics of the neutron meters in the pre-sent work. The fitting results show that the H*(10)＇dir values of the meters are in good agreement within the theoretical data within 4%. The averaged CFs of the three neutron meters were evaluated as 0.99 ± 0.01, 1.00 ± 0.03, and 0.99 ± 0.08, respectively. The largest standard uncertainty of these values was determined to be approximately 18.47% (k＝1). The standard uncertainty of the CFs obtained using the RFM method was less than 4.23% (k＝1), which is the smallest uncertainty among the three methods.