Measurements of the influence of the magnetic field on conductivity of martensite films NiМnGа have been carried out. We researched the films 0,1, 0,2, 0,4, 0,6, 1 and 5 microns thick that were obtained by magnetron sputtering on glass and polycrystalline substrate Al2O3. For evaporation we used alloy target Ni49,.5Мn28Gа22,.5 and Ni52Мn24Gа24. After evaporation, the films were annealed in vacuum for two hours at the temperature 873 K and 1273 K. According to X-ray spectroscopy the non-annealed films presented a hard substitution alloy on the basis of GCK lattices Ni with the period h=0,3620 nm. The average size of particles on the substrate of Al2O3 formed about 10 nm. The non-annealed films on the glass substrates were even more subdispersed. After annealing, the size of crystalline particles increased on the glass substrates up to 30 microns and up to several microns on the substrates of Al2O3. On the substrates of Al2O3 the quantity of single crystals in annealed films increases with the growing of the thickness of the film. Besides, for the films of Ni49,.5Мn28Gа22,.5 it is much more than for the films of Ni52Мn24Gа2. Conductivity of the non-annealed films changes with the growth of temperature from 0 to 1500C and does not depend on the composition of the film and its thicknesses. At the temperature close to the temperature of the martensite transition T~340 K, practically in all films a dog-leg of direct dependency R=f(T) is observed, which can be connected with the possible phase transition. The general change of specific resistance in nonannealed films within the temperature range of 0-1500C is about 2%. After annealing, the temperature dependence of the film conductivity changes from negative to positive; it also changes its character and absolute value. At the same time, typical points corresponding to the martensite transition appear and the dependency diagram R=f(T) acquires an N-like form. For the films annealed at 1273K the value of intense decrease of resistance is much more than for the films annealed at the temperature 873K. The beginning of martensire transformation in the annealed films Ni49.5Мn28Gа22.5 occurs at T~328K and it ends at T~333K. During heating and cooling a small hysteresis of about 2K is observed. For the films of the Ni52Мn24Gа24 the transition temperature increases – the beginning at T~333K, the end at T~338K. In addition, the temperature dependence of the resistance in austenitic phase is observed – the resistance increases much slower than in the films Ni49.5Мn28Gа22. For these films hysteresis value also increases ~5K. Film conductivity depends not only on the value and directions of the external magnetic field. Moreover, for the annealed films the resistance value changes intensively R≤ 10% even in weak magnetic fields when the magnetic field direction changes from the direction along the film plane to the direction perpendicularly the film plane. The value of magnetic resistance depends on the film temperature and the maximum value R is observed in the interval between the beginning and the end of the martensite transition when martensite and austenitic phases exist simultaneously in the film.