Narrow band images covering strong emission lines are efficient to survey supernova remnants ( SNRs ) in nearby galaxies .
Using the narrow band images provided by the Local Group Galaxy Survey we searched for SNRs in M33 .
Culling the objects with enhanced [ S ii ] /H \alpha and round morphology in the continuum-subtracted H \alpha and [ S ii ] images , we produce a list of 199 sources .
Among them 79 are previously unknown .
Their progenitor and morphology types were classified .
A majority of the sample ( 170 objects ) are likely remnants of core-collapse SNe , and 29 are remnants of Type Ia SNe .
The cumulative size distribution of these objects is found to be similar to that of the M31 remnants derived in the similar way .
We obtain a power law slope , \alpha = 2.38 \pm 0.05 .
Thus a majority of the sources are considered to be in the Sedov-Taylor phase , consistent with previous findings .
The histogram of the emission line ratio ( [ S ii ] /H \alpha ) of the remnants has two concentrations at [ S ii ] /H \alpha \sim 0.55 and \sim 0.8 , as in M31 .
Interestingly L _ { X } ( and L _ { 20 cm } ) of the compact center-bright objects are correlated with their optical luminosity .
The remnants with X-ray emission have brighter optical surface brightness and smaller diameters than those without X-ray emission .