Leicestershire 1 was a tier 10 English Rugby Union league with teams from Leicestershire taking part.

When league rugby began in 1987, this division contained the following teams: The original Leicestershire 1 was a tier 8 league.

At the end of the 1991–92 season all of the East Midlands and Leicestershire leagues were merged and most sides in Leicestershire 1 transferred to the new East Midlands/Leicestershire 1.

[f] After an absence of four seasons Leicestershire 1 was reintroduced, this time sitting at tier 10 of the league system.

Remerging of all the East Midlands and Leicestershire leagues meant that Leicestershire 1 was cancelled at the end of the 1997–98 season and the majority of teams transferred into East Midlands/Leicestershire 2.