Since most of the spectrum used for commercially purposes, such as : cellular communications, radio and television broadcasting, broadband wireless access communications, looks like there is a gap for Public Safety Communications purposes. Public Safety communications today left behind if we compare to cellular communications for example. Cellular communications grow according to the need of people for mobility, and broad band. Evolution of the network from narrow band to broadband make more faster in the commercial communications purposes than in the Public Safety Communications field. Legacy of lack of planning and lack of strategy by the Government on Public Safety Communications, a problem should face today. They build their own network, used spectrum with their own network as shown in the Table 1 and Fig.3. The fragmented approach should be studied. Government should quaranted among the agencies could communicate easily and could give services to people. This paper analyze interoperability problem with Public Safety Communications network and give one solution with using 700 MHz band as a common frequency band. The common frequency band is one of stage as shown in Fig.2 as a solution for interoperability gap. Fig. 4 is Indonesia's Band Plan of Digital Dividend. The portion of 700 MHz frequency band for Public Safety is shown in Fig. 5. 700 MHz is one of future frequency band for Public Safety Communications in some countries.