the subsea xmas tree according to the present invention a more detailed example of embodiment will now be described with reference to fig1 fig1 is a cross sectional schematic view of a vertical subsea xmas tree 1 arranged on the sea floor on top of a subsea well the xmas tree 1 has an inner bore 3 for conducting hydrocarbons from the well in order to prevent the xmas tree components in the region within a wellhead 5 and above a tubing hanger 6 from being excessively heated a cooling means 7 is arranged to the xmas tree 1 the cooling means 7 comprises a fluid conducting pipe 9 the pipe 9 has an inlet 9 a guiding cooled cooling fluid into the xmas tree 1 and an outlet 9 b guiding heated cooling fluid out of the xmas tree 1 the pipe 9 also has a radiator part 9 c adapted for effective heat convection to the ambient sea water it should be noted that a substantial part of the pipe 9 has a vertical extension this results in a siphon effect in the cooling fluid since the colder cooling fluid has larger density than the warmer cooling fluid this principle is well known to a man skilled in the art thus by arranging the pipe 9 with such a vertical extension the need for a pump to provide circulation of cooling fluid is avoided preferably the pipe 9 has a vertical part 9 d extending in a substantially straight manner beside the radiator part 9 c on an upper side of the pipe 9 there is arranged a valve 11 and an inlet port 13 for accessing the interior of the pipe 9 the pipe channel may also be connected.