Midfielder Michael Williams arrives from Matlock Town, following his team-mate left-back Bradley Beatson to the Home of Football.
Williams, 25, joined the Gladiators from Ilkeston Town back in 2016 and scored 24 goals in 110 appearances for the club.
Manager Gavin Smith has also pulled off a coup with the signing of prolific striker Karl Demidh from Loughborough Dynamo.
Smith said: “Karl is a massive signing for The Club, we had to fight off a lot of teams to get Karl to sign.
“He’s a proven goal scorer in this league and above. He’s got a great attitude and quality - he can hold the ball up, run in behind, he scores goals, wants to win trophies and is the sort of player we needed to be bringing to the Sheffield FC.
“Karl scored over 20 goals last season at Loughborough and I know he will score lots of goals for us if we provide him with the chances.”