Sergeant Peter Rayner, 34, from Bradford, West Yorkshire, of 2nd Battalion The Duke of Lancaster's Regiment, was killed on Friday.
The soldier was carrying out a patrol in the Nahr-e Saraj area of Helmand Province.
The number of British military personnel killed in operations in Afghanistan since 2001 is now 340.
Sgt Rayner's wife Wendy led tributes to the "fantastic" and "loving" husband and father to son, Derek.
"He loved his job and doing something which he believed in.
"He will be sincerely missed by all who knew him," she said.
Sgt Rayner was born into a military family, and his parents Peter and Bernadette said their son was "always full of energy and was someone who enjoyed life to the full".
"As a soldier he loved his job and was totally committed to the Army, as well as his family and friends.
"As a son and brother, he was a fun-loving and caring person of whom we are all very proud.
"We loved him so dearly and will miss him with all our hearts."
The MoD said Sgt Rayner, who had also served in Bosnia and Iraq, would be "sorely missed" and remembered for his "pre-eminence as a Javelin Commander, for his forthright manner and for his huge personality".
Sgt Rayner's bravery and courage had attracted much praise in Afghanistan, it said.
Lieutenant Colonel Robbie Boyd, Commanding Officer 2nd Battalion, The Duke of Lancaster's Regiment, said: "He was honest, loyal and always vocal.
"A true Lion of England and a man of high morals, guts and integrity.
"A man who cared not just for the morale of his soldiers, but in how that morale was created.
"A man with great spirit and forthrightness, who was as true as his aim was with a Javelin Missile."
Major Paul Tingey, Officer Commanding Arnhem Company, 2nd Battalion, The Duke of Lancaster's Regiment, said Sgt Rayner left a "lasting impression" on people.
"He spoke his mind and always had the best interests of his men at heart.
"He was someone that you could rely on to tell you exactly what he thought. I always welcomed his words of advice.
"I will remember Skippy as a devoted family man, a fanatical mountain biker and one of the best commanders that I have had the privilege to work with," he said.

The giant orb, covered in detailed NASA imagery of the lunar surface, was created by Bristol-based Luke Jerram.
Titled Museum of the Moon, it has been hung temporarily in the Wills Memorial Building to welcome the university's new chancellor Sir Paul Nurse.
Mr Jerram, said: "This is an opportunity for the public to have a close encounter with the moon."
Images taken by a NASA satellite were used by the artist to create the installation.
Each centimetre of the internally-lit spherical structure represents 5km (3 miles) of the moon's surface.
Mr Jerram, who was behind Bristol's 2014 water slide and the globally successful street pianos, said it would give people the chance to "study every detail of its surface" as well as "bathe in moonlight".
"The Great Hall is such an amazing space to present the Museum of the Moon," he said.
The floating artwork, which is illuminated and accompanied by music from different composers, was created in partnership with the University of Bristol and the UK Space Agency.
The Great Hall will be open to the public to view the Museum of the Moon next weekend.
A British soldier killed in an explosion in southern Afghanistan has been named by the Ministry of Defence.
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A 7m (23ft) diameter giant replica of the moon has been installed in the University of Bristol's Great Hall.