Hmm. Not the best.
Nice concept, but it got old real fast. I played a number of levels and nothing new happened at all.
There needs to be progression in a game like this, so consider adding challenges (like bombs that you can't pick up, fish snapping the line etc.) also include bonuses for the harder-to-catch coins - why is the large, easy coin worth the same as the tiny ones? And how much do I need to win the game? (I gave up after a number of the same levels).
If you use music on a loop, you need to make it MUCH longer, not the same notes repeated over and over. Without a mute button, this really grated on me! The animation isn't wonderful either, and the collision detection is awful - the hook went straight through a number of the smaller coins without catching them. I also dislike the character, his 'hihi's got annoying very fast and reek of poor translation.
It's a nice idea for a game, but to give it any sort of longevity there needs to be something interesting that happens, a level progression that makes things harder for the player. As it is, it's just a game about mouse-clicking.