A dual polarized (DP) 2 × 2 MIMO antenna with high gain and isolation is proposed for WLAN band (IEEE 802.11a/b/g/n) and C-band (spectrum sharing) applications. The proposed MIMO antenna design consists of two DP pentagonal microstrip elements. A slot on a ground is introduced to escalation the isolation among two antennas. The measured frequency bands extend from 2.43 to 2.54 GHz, 4.05 to 4.13 GHz and 5.22 to 5.37 GHz with VSWR <2. The achieved isolation between two ports is more than 30 dB. The measured peak gains at 2.45 GHz, 4.09 GHz and 5.29 GHz resonant frequencies are 7.95 dBd, 3.39 dBd and 4.18 dBd, respectively. The RT druid 5880 substrate is used for fabricating the MIMO antenna. Measured results agree with the simulation ones. The diversity performances in terms of diversity gain (DG), efficiency, and envelope correlation coefficient (ECC) have also been reported. The proposed MIMO antenna is tested using Wi-Fi router. © 2019, Springer Nature Switzerland AG.