The 1999 London Broncos season was the twentieth in the club's history and their fourth season in the Super League.

The Broncos had three coaches over the course of the season, competing in Super League IV and finishing in 8th place.

The club also made their maiden appearance in the final of the Challenge Cup.

Sources:[1][2] Source:[3] The London Broncos progressed to the Final of the Cup, before losing to the Leeds Rhinos by 52–16 at the Old Wembley Stadium in London.

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