We prepared the Bi 2 Sr 2 Ca n - 1 Cu n O y (BSCCO) films by rf magnetron sputtering using mixture of helium and oxygen (He:O 2 =4:1) as a sputtering gas. The Bi 2 Sr 2 CaCu 2 O y thin films were easily prepared, and the compositions of the films were approximately equal to that of the targets deposited by this sputtering method. In the film prepared using the single powder targets with the composition of Bi:Sr:Ca:Cu=2:2:2:3, the Bi 2 Sr 2 Ca 2 Cu 3 O y phase was dominant at T s u b =630 o C. In addition, the gas pressure effectively improved the crystallinity and superconductivity of the films.Therefore, to use sputtering gas of helium and oxygen mixture is thought to be effective for the control of the composition in the BSCCO films.