How to Cook Corn on the Cob in a Pressure Cooker
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Different makes and models vary somewhat, but in general, to cook corn on the cob in a pressure cooker, husk and desilk a half-dozen ears of corn. Put a cup of water in the pressure cooker, put the trivet or steamer basket that came with the pressure cooker in the bottom, and put the corn on top. Put the pressure cooker over medium-high heat, and use whatever method your pressure cooker has for recognizing that it has come up to pressure. Lower the heat to medium and let cook for two to three minutes.

Because corn (and other vegetables) cooks so quickly in the pressure cooker, you want to release the pressure quickly when the time is up. With most types of pressure cookers, this involves carrying the beast carefully to the sink, tipping it a few degrees, and allowing cold water to trickle over the top (but keeping it away from the pressure valve). The pressure will dissipate in a couple of seconds (you may hear a decompressing sound — almost like a swooshing "pop" — once the pressure has been released). At this point, you can open the pressure cooker and remove the corn.