My Prius honks at me

Every time? How do you lock it?

Simple possibilities: car was not shut OFF when you left it, or door or rear hatch were not completely closed; but in these cases it will also honk at you when you try to lock it and walk away. Other simple possibility: you accidentally push the alarm button on the fob when walking up to the car.

 

It should not do this.
Just to clarify: It is the horn honking? As in "Panic" button being pushed?

There have been a couple of posts about the panic button getting pushed while in a pocket or purse and this would get cancelled by the steps you mentioned.

I guess it's possible that your panic button on the fob is extremely sensitive or even stuck. Try the other fob while your regular fob is well out of range and see if you have the same results.

 

I was one of the posters who has a problem with the Panic button on the fob being pressed when it was in my pants pocket or in my hand. It still happens and it scares me and drives me nuts. When the car goes in for the Steering recall I will ask them to disable the panic button with the scan tool. It can be done but I want to see if this also disables the horn if someone tries to break in. I bet that the "sensitive" panic button on the fob is the cause of this poster's problem also.