This paper presents a simple but novel circular ring slotting technique into rectangular microstrip antenna of making a compact patch which works in four frequency band. This compact microstrip antenna realized by changing the geometric shape, obtained by inserting small circular slots. The simulation has been performed by simulation software GEMS version 7.71.01 and using Taconic TLY-5 dielectric substrate with relative permittivity 2.2 and height 1.588mm. The simulated return losses are obtained −23.92dB, −10.71dB, −15.12dB and −13.38dB at 6.7GHz, 10.85GHz, 14.15GHz and 19.50GHz respectively. Therefore, this antenna can be applicable for C-band, X-band, Ku-band and K-band applications respectively.