A sliding door comprising: - a door arranged to slide, in use, between extreme positions of a door opening of a vertical wall, - a top profile securable to the door of the sliding door, and - a support device arranged to guide and support the door, and comprising - a frame element securable to a vertical wall, characterized in that the support device further comprises - a support guide arranged to be moved and adjusted in vertical direction with respect to the frame element, - a guide and support component fixed to the support guide and comprising at least one idle wheel (401, 402) arranged to guide and support, in use, the top profile, said guide and support component being arranged to be moved and adjusted in vertical direction as to said frame element by way of an adjustment element, - an anti-releasing component fastened to the support guide, said anti-releasing component, comprising a lever and being arranged to be moved and adjusted in vertical direction as to the frame element by way of said adjustment element, whereby by moving and adjusting in vertical direction said guide and support component it is provided that said at least one idle wheel (401, 402) of said guide and support component is brought into contact with said top profile and said anti-releasing component is automatically brought into engagement with said top profile by way of said lever. - a door arranged to slide, in use, between extreme positions of a door opening of a vertical wall, - a top profile securable to the door of the sliding door, and - a support device arranged to guide and support the door, and comprising - a frame element securable to a vertical wall, characterized in that the support device further comprises - a support guide arranged to be moved and adjusted in vertical direction with respect to the frame element, - a guide and support component fixed to the support guide and comprising at least one idle wheel (401, 402) arranged to guide and support, in use, the top profile, said guide and support component being arranged to be moved and adjusted in vertical direction as to said frame element by way of an adjustment element, - a frame element securable to a vertical wall, characterized in that the support device further comprises - a support guide arranged to be moved and adjusted in vertical direction with respect to the frame element, - a guide and support component fixed to the support guide and comprising at least one idle wheel (401, 402) arranged to guide and support, in use, the top profile, said guide and support component being arranged to be moved and adjusted in vertical direction as to said frame element by way of an adjustment element, - an anti-releasing component fastened to the support guide, said anti-releasing component, comprising a lever and being arranged to be moved and adjusted in vertical direction as to the frame element by way of said adjustment element, whereby by moving and adjusting in vertical direction said guide and support component it is provided that said at least one idle wheel (401, 402) of said guide and support component is brought into contact with said top profile and said anti-releasing component is automatically brought into engagement with said top profile by way of said lever.