We present the results of an optical search for Supemova Remnants (SNRs) in the spiral galaxies NGC6946 and NGC628. The SNR identification technique consisted of constructing continuum-subtracted H-alpha and [SII] lambda lambda 6716,6731 images and then using [SII] / H-alpha ratios obtained from the image. 32 emission nebulae have been detected as SNR candidates in NGC6946. 22 of them were previously identified by Matonick et al (1997). We found five SNR candidates in the spiral galaxy NGC628. We will compare and contrast the new SNR candidates and our optical data with the existing Chandra and XMM observation of the two galaxies of interest and VLA radio observation of NGC6946. Interference-filter CCD images of two spiral galaxies were taken in 2004 September with the f/7.7 1.5 m Russian-Turkish Telescope at Turkish National Observatory.