i am planning to travel to Taipei in Mid Feb 2017 and i hear this period will be a raining period.

Oh, according to the previous statistics, the temperature may range from 45 F to 60 F. There may have several light rainy days. It won't influence the sightseeing a lot. You are advised to prepare jackets, long-sleeved shirts, jeans and pants. Remember to bring the rain gear.