Humidity sensors using various NASICON materials were experimentally produced by a thick film printing method. Among the NASICON materials, a humidity sensor using Na₄Zr₂Si₃O₁₂ material showed comparatively lower resistance in low humidity. The relation between a logarithm of its resistance and relative humidity was almost linear and showed nonhysteresis (2M-10kΩ in a range of 20-90%RH). Also, the humidity sensor using Na₄Zr₂Si₂O₁₂ in comparison with one using a usual NASICON was improved on the stability of a long term and durability in various environment tests.