A trolley for inspecting railway construction parameters comprising: - a central body - a left frame joined with the central body on the left side of the central body - a right frame joined with the central body on the right side of the central body - a left running assembly mounted on the free end of the left frame transversely to the left frame and wherein this left running assembly is provided with a series of wheels (3.1) - a right running assembly mounted on the free end of the right frame transversely to the right frame and wherein this right running assembly is provided with a series of wheels (4.1) - a telescopic column joined at the lower end thereof with the central body - a tray joined to the free end of the telescopic column - a handle joined to the free end of the telescopic column wherein - the left frame and the right frame are joined with the central body by means of articulated joints (1.2, 2.2), said articulated joints (1.2, 2.2) being made by hinges foldable 90o with respect to the working position thereof until the left frame and the right frame are parallel with each other, - the left running assembly and the right running assembly are joined in an articular manner with respect to the free end of the left and right frames, respectively, such that they are foldable 90o with respect to a vertical axis until each running assembly (3, 4) is aligned with and underneath the frame (1, 2) it is joined to, - the tray is foldable until it is touching the telescopic column - the telescopic column is joined at the lower end thereof in an articular manner with the central body - the articulated joints are designed such that the cables which pass through them are protected at all times and said cables are long enough so that the trolley can be folded and unfolded. - a central body - a left frame joined with the central body on the left side of the central body - a right frame joined with the central body on the right side of the central body - a left running assembly mounted on the free end of the left frame transversely to the left frame and wherein this left running assembly is provided with a series of wheels (3.1) - a right running assembly mounted on the free end of the right frame transversely to the right frame and wherein this right running assembly is provided with a series of wheels (4.1) - a telescopic column joined at the lower end thereof with the central body - a tray joined to the free end of the telescopic column - a handle joined to the free end of the telescopic column wherein - the left frame and the right frame are joined with the central body by means of articulated joints (1.2, 2.2), said articulated joints (1.2, 2.2) being made by hinges foldable 90o with respect to the working position thereof until the left frame and the right frame are parallel with each other, - the left running assembly and the right running assembly are joined in an articular manner with respect to the free end of the left and right frames, respectively, such that they are foldable 90o with respect to a vertical axis until each running assembly (3, 4) is aligned with and underneath the frame (1, 2) it is joined to, - the tray is foldable until it is touching the telescopic column - the telescopic column is joined at the lower end thereof in an articular manner with the central body - the articulated joints are designed such that the cables which pass through them are protected at all times and said cables are long enough so that the trolley can be folded and unfolded.