Man-of-the-match Saunders' second goal in three games stretched the Daggers' impressive unbeaten home record to seven games at the expense of the misfiring Bees.
Defeat for Barnet was their third away loss in a row, with the relegation-strugglers having now not won in their last five matches.
The impressive Sam Williams laid off for Saunders to rifle home into the roof of the net after a bright opening from the hosts.
Luke Wilkinson struck the bar with a stinging drive as John Still's side came within a whisker of doubling their advantage shortly after the half-hour mark.
Michael Spillane headed over from close range and rifled wide of the left upright as Still's team dominated proceedings.
Barnet goalkeeper Graham Stack produced a smart save to deny Williams in the 68th minute, but no matter how hard the Daggers tried they could not get a second goal to make their victory more comfortable.