To obtain an absorber of absorption refrigerating machine in which refrigerant vapor can be absorbed surely into absorbing solution.

The absorber comprises an upper tank 11 having an inlet 15 being supplied with solution L for absorbing refrigerant vapor G, a lower tank 13 having an inlet 17 being supplied with refrigerant vapor G, an outlet 19 for discharging the solution L which has absorbed the refrigerant vapor G, a tube 21 disposed between the upper tank 11 and the lower tank 13 with the upper and lower end parts 21a, 21b thereof being inserted, respectively, into the upper and lower tanks 11, 13, and an inlet member 27 disposed at the upper end of the tube 21 and introducing the absorbing solution L to the inner wall face 21d of the tube 21.