The Premier League side were forced to settle for a draw against their League One opponents, following Andy Williams's deflected second-half equaliser at the County Ground.
Bale collected a neat through pass from Gylfi Sigurdsson and fired the ball into the top corner from 18 yards to give Spurs the lead on 15 minutes.
The PFA Player of the Year, who found the net 26 times for his club last season, had earlier come close to opening the scoring in the second minute, but he was denied by goalkeeper Wes Foderingham.
Tottenham, who named a strong starting XI, went close again from the resultant corner, as Jermain Defoe's flicked effort struck the crossbar.
The second half was preceded by a deluge of substitutions, which led to a disjointed and unattractive 45 minutes.
Spurs continued to dominate possession, but their defence was undone by a quick, and somewhat fortunate, counter-attack with 15 minutes remaining.