Your URL isn't encoded, it looks like it was encoded because it uses non-ASCII/non-Latin characters, any URL that has another URL inside as a parameter needs to be encoded, long story short, here is the solution:
function urlShare(url,title,appkey){
return 'http://share.v.t.qq.com/index.php?c=share&a=index&url='+encodeURIComponent(url)+'&title='+encodeURIComponent(title)+'&appkey='+appkey
}
Just call this function with the URL, Title and appkey (don't know if the appkey need to be encoded):
urlShare('http://www.testurl.com/product/this-is-a-product-%E7%9F%AD%E8%A3%A4','A Title','id-000000')
It will return a safe URL that actually works.