The invention provides a cooling structure for a bearing pedestal of a steam exhaust cylinder exhausting steam axially. The bearing pedestal is located in a steam exhaust cylinder shell. Supporting legs penetrating out of the steam exhaust cylinder shell are fixed to the bearing pedestal. The part, located in the steam exhaust cylinder shell, of each supporting leg is sleeved with a heat shield. Preferably, a cooling channel is formed by the space between each heat shield and the corresponding supporting leg. The two ends of each cooling channel are communicated with the outside and an extraction opening located in the steam exhaust cylinder shell respectively. Each extraction opening is communicated with an air extraction mechanism. According to the cooling structure for the bearing pedestal of the steam exhaust cylinder exhausting the steam axially, lubricating oil pipelines are integrated into the supporting legs of the bearing pedestal, and no extra through-flow area is occupied; meanwhile, the advanced structural design of the forced convection cooling supporting legs is adopted, steam extraction by shaft seals and air extraction by fume exhaust pipes are adopted for guiding air to flow, the supporting legs are cooled through forced surface convection heat exchange, most heating effects brought by lubricating oil and exhaust steam to the bearing pedestal are counteracted, and stabilization of the shafting elevation is ensured.