Absorber is a key component of absorption refrigeration system, in which there is a complicated heat and mass transfer. To improve the performance of absorber, the magnetic field was used as a enhancing way, the experiments of NH3/H2O bubble absorption in magnetic field were carried out. The results showed that the NH3/H2O bubble absorption can be strengthened by the magnetic field. Both AR(absorption rate) and EAR(effective absorption ratio) increase with the increase of magnetic intensity within the range of 0~280mT. The EAR is always higher than 1 when the external magnetic field exists. The EAR reaches the maximum 1.069 when the initial ammonia concentration is 20wt% and the magnetic intensity is 280mT. The primary strengthening mechanisms are also explained.