The structure in the picture shows that it contains a tablet with writing on it. If you have higher-rez picture, I can try to read the writings.
But based on the fact that it has what looks like concrete steps at its bottom, I am going to guess that this is a relatively recent structure erected by the people who established the park, probably to document some information about the history of the temple.
At the lower left corner of the picture, there is a building that could be the ticket office / entrance to Bulguksa. So I am guessing this structure probably is on the plaza in front of the entrance.