Any Halal restaurant near Park Plaza Beijing Wangfujing

Well, yes. I know two Halal restaurants nearby:
one is Jinxuanzhai Halal Resaurant, whose specific location is Lishi Hutong, Dongsi South Street, Dongcheng District.
The other is Halal Restaurant at No. 23, Yanyue Hutong, Dongcheng District.
Both of them are about 500-600m from the hotel, so you can walk there by asking for the exact directions.