This would raise the final temperature.
I assume that you are doing a calorimetry experiment in which you place a hot metal in 100 g of water and measure the increase in temperature.
Now, assume that you repeat the experiment with 50 g of water.
The metal still has the same amount of heat to transfer.
However, there is only half as much water.
So, to absorb the same quantity of heat, its temperature increase will have to be about twice as much as when there were 100 g of water.