It is aimed to provide a resonator type SAW filter having a relatively wide fractional bandwidth by canceling and decreasing reflection coefficients of electrode fingers each other with a ¼ wavelength electrode in a multi-longitudinal-mode-coupled resonator type SAW filter. The resonator type SAW filter includes, on a piezoelectric substrate, an input interdigital transducer that excites a surface acoustic wave, an output interdigital transducer that receives the surface acoustic wave excited by the input interdigital transducer, a control interdigital transducer interposed between the input interdigital transducer and the output interdigital transducer that controls a state of the surface acoustic wave, and a pair of reflectors arranged on outer sides of both the input interdigital transducer and the output interdigital transducer. And, the input interdigital transducer, the output interdigital transducer, and the control interdigital transducer alternatively arrange two different zones C and E. An electrode period length P is set as PC and a number of pairs MC of the electrode fingers is set to 1 in zone C and the electrode period length P is set as PE and a number of pairs ME of the electrode fingers is set to 1 in zone E on the condition that the electrode period length P as a sum of an electrode finger width L and a spacing S between the electrode fingers is equal to L+S. The electrode fingers in zones C and E are all connected to a feeder conductor. As a result, a multi-longitudinal-mode-coupled resonator type SAW filter having a small insertion loss, and a wide fractional bandwidth of 2000 to 4000 ppm is achieved by canceling and decreasing sums of reflected waves from the electrode fingers in zones C and E, and decreasing the effective reflection coefficient per the electrode finger.