We have measured the strain-resistance characteristics of some non-magnetic and magnetic metal films. In order to suit to the objective of this article, we have chosen the Pd film as an example for the non-magnetic film, the Fe 2 1 Ni 7 9 film for the magnetic film with a positive magnetostriction (λ s >0), and the Co 2 0 Ni 8 0 film for the magnetic film with λ s <0. The thickness t f of the films ranged from 40 to 1500Å. The strain gauge factor γ of the Pd film was obtained from the linear strain-resistance plot. Then, γ is expressed as a function of the sheet resistivity R s q . For the magnetic films, only when the film is saturated either longitudinally ( ) or transversely ( ) by an external field, is the strain-resistance plot linear. While in a zero-field, the strain-resistance plot becomes non-linear. From the former, we could obtain γ or γ , and from the latter, we could obtain γ a p . γ or γ is of the same order of magnitude as γ. However, γ a p is abnormally large, due to the magnetoelastic and the anisotropic magnetoresistance effects. In addition to the piezoresistance data, we also found the critical thickness (t f c ) for the electrical coalescence and that (t f m ) for the magnetic coalescence. Usually, for the same magnetic material, t f m >t f c . The coalescence ability is the best for the Co 2 0 Ni 8 0 films, and the worst for the Pd films.