Neptune doesn't have a surface, because is it a gas giant. The average temperature of Neptune is around -218°C (-360.4°F).
The temperature on Neptune's surface ranges from 72 Kelvin to 55 Kelvin. This is the equivalent of -201 degrees Celsius to -218 degrees Celsius.
-200 °C
Technically speaking, Neptune is the planet with the lowest surface temperature; however, Neptune does not have a solid surface.
The lowest surface temperature is Jupiter. 
The planet Neptune's south pole is the current region facing toward the sun. As such it is the warmest part of Neptune featuring temperatures about ten degrees warmer than the rest of the planet whose average temperature is -200 Celsius.
There are a variety of interesting facts about the planet Neptune. There are 14 moons of Neptune, and the surface temperature is about -201 degrees Celsius.
Pluto is actually colder than Neptune at 33K. Neptune's surface temp drops to 72K and Uranus' drops to 76K. While Neptune should be much colder, it is thought to have a very high internal temperature.
The surface temperature on Neptune is very very cold. it is - 391 F.
Technically speaking, Neptune is the planet with the lowest surface temperature; however, Neptune does not have a solid surface.
The average surface temperature of Neptune is 330 degrees Fahrenheit.
The average surface temperature is 72 K.
The lowest surface temperature is Jupiter. 
Core, Surface , Temperature.
The planet Neptune's south pole is the current region facing toward the sun. As such it is the warmest part of Neptune featuring temperatures about ten degrees warmer than the rest of the planet whose average temperature is -200 Celsius.
i think 184 degrees Celsius
There are a variety of interesting facts about the planet Neptune. There are 14 moons of Neptune, and the surface temperature is about -201 degrees Celsius.
It is cold all of the time, with temperature always in the negatives.
Pluto is actually colder than Neptune at 33K. Neptune's surface temp drops to 72K and Uranus' drops to 76K. While Neptune should be much colder, it is thought to have a very high internal temperature.
The average temperature on Neptune is -353°F (-214°C)