This paper presents a rectangular spiral microstrip antenna operate in multi-band between the frequency ranges of 0.5–5.0 GHz. The proposed rectangular spiral microstrip antenna will be light weight, flexible, slim and compact unit compare with current antenna used in these bands. The paper also presents the detail steps of designing the rectangular spiral microstrip antenna and at different iteration level. This paper is also present how to increase no of bands and return loss of rectangular spiral microstrip antenna. IE3D software is used to compute the S11, VSWR and Smith chart of the antenna
