Why not set the object's position?

Sorry for Google Translator

local player = game.Players.LocalPlayer
local charecter = player.Character
local mouse = player:GetMouse()

mouse.Button1Down:connect(function()
	local stone = game.ReplicatedStorage.stone:Clone()

	if mouse.Target ~= nil then
		stone.Parent = workspace
		stone.Position = Vector3.new(mouse.Target)
	end
end)
	

What have I done wrong? if you remove the line

stone.Position = Vector3.new(mouse.Target)

, the code works well. According to my idea object "stone" should be created on the mouse coordinates

The problem is here is that you're using wrong properties of mouse!

Since using mouse.Target.Position will return the coordinates of object that the mouse it pointing at. While mouse.Hit.p will return the coordinates of where your mouse is pointing which is what you want, correct?

So change line 10 to: stone.Position = mouse.Hit.p