In the United States of America the natural gas which contains about 0.4% up helium content is used as main material for producing the helium gas. The equipment recently developed in France separates and rectifies 0.05% of helium gas to produce high purity of helium gas. This will serve as a good reference to how to go on with developing the helium resources in Japan.The long and continuous operation of helium liquefier and refrigerator depends upon settling a problem that the impurities in helium gas is accumulated in the heat exchanger, as well as the good performance of compressor and turbine. We explain the present condition regarding the adsorbing method mainly adopted for purifying the helium gas. We have described so far the measuring principle and accuracy of the various analizers, like those for trace oxygen, nitrogen, moisture, methane and carbon doixide gas, as those closely related to the impurities in helium gas. Further we have discussed the comparison of various methods in case of purging the air in the air-tight vessels by using the helium gas, and the course of impurities entraining into the helium equipment having been examined.