A driving assistance device for a railway vehicle, comprising means for determining a target speed (V c), including: - means for comparing an instantaneous speed (V i) of the railway vehicle with the target speed (V c) or with an interval around the target speed, and - progressive means for indicating driving instructions for a conductor of the railway vehicle, said driving instructions including instructions (25, 26, 28, 30) for modifying the instantaneous speed (V i) in order to bring it closer to the target speed (V c), the indicating means being configured to: - indicate an instruction to increase the speed when the instantaneous speed (V i) is below a first predefined value, the instruction to increase the speed including an indicator with a variable value depending on the difference between the instantaneous speed (V i) and the target speed (V c), - indicate an instruction to decrease the speed when the instantaneous speed (V i) is above a second predefined value, the instruction to decrease the speed including an indicator with a variable value depending on the difference between the instantaneous speed (V i) and the target speed (V c), and - indicate an instruction to maintain the speed when the instantaneous speed (V i) is comprised between the first and second predefined values, and wherein the indicating means include a display panel, able to display the driving instructions (25, 26, 28, 30), or a head-up display device, able to display the driving instructions (25, 26, 28, 30) in a field of view of the driver, and characterized in that the indicating means are configured to: • display an icon for an instruction to increase the speed when the instantaneous speed (V i) is below a first predefined value, the icon for the instruction to increase the speed comprising the variable value indicator, formed by an element with a variable height depending on the difference between the instantaneous speed (V i) and the target speed (V c), and • display an icon for an instruction to decrease the speed when the instantaneous speed (V i) is above a second predefined value, the icon for the instruction to decrease the speed comprising the variable value indicator, formed by an element with a variable height depending on the difference between the instantaneous speed (V i) and the target speed (V c). - means for comparing an instantaneous speed (V i) of the railway vehicle with the target speed (V c) or with an interval around the target speed, and - progressive means for indicating driving instructions for a conductor of the railway vehicle, said driving instructions including instructions (25, 26, 28, 30) for modifying the instantaneous speed (V i) in order to bring it closer to the target speed (V c), the indicating means being configured to: - indicate an instruction to increase the speed when the instantaneous speed (V i) is below a first predefined value, the instruction to increase the speed including an indicator with a variable value depending on the difference between the instantaneous speed (V i) and the target speed (V c), - indicate an instruction to decrease the speed when the instantaneous speed (V i) is above a second predefined value, the instruction to decrease the speed including an indicator with a variable value depending on the difference between the instantaneous speed (V i) and the target speed (V c), and - indicate an instruction to maintain the speed when the instantaneous speed (V i) is comprised between the first and second predefined values, • display an icon for an instruction to increase the speed when the instantaneous speed (V i) is below a first predefined value, the icon for the instruction to increase the speed comprising the variable value indicator, formed by an element with a variable height depending on the difference between the instantaneous speed (V i) and the target speed (V c), and • display an icon for an instruction to decrease the speed when the instantaneous speed (V i) is above a second predefined value, the icon for the instruction to decrease the speed comprising the variable value indicator, formed by an element with a variable height depending on the difference between the instantaneous speed (V i) and the target speed (V c).