The organisation, which monitors Israeli human rights violations in the occupied territories, described Monday's conviction of an Israeli soldier for the killing of British photographer and activist Tom Hurndall as an "exception than the norm".
"It is obvious that the prosecution and conviction of Tom Hurndall's killer represents the exception, not the norm, as it is amply clear that the Israeli army refrains from investigating most cases involving the killing of Palestinians civilians by the Israeli army," said a report released by B'tselem on Monday.
The report pointed out that since September 2000, the Israeli army killed as many as 1722 Palestinian civilians who played no part in the hostilities. Those killed included 536 children.
The report said that the Office of Military Prosecutor initiated investigations into no more than 108 cases of controversial shootings and that in no more than 19 cases the perpetrators were indicted.
The report said only two Israeli soldiers were convicted of unlawfully killing Palestinians.
Sergeant Taysir Hayb fatally
shot a British photographer
In two other cases, soldiers were convicted of intentionally vandalising Palestinian property.
"These data are not coincidental but rather a result of the firing instructions which encourage soldiers to pull the triggers."
"We have seen a clear policy of whitewashing crimes by refraining from investigating them. This is how the Israeli army teaches to view lightly Palestinian lives," said the report.
Earlier during the day, an Israeli military court found a soldier, Taysir Hayb, guilty of the manslaughter of Hurndall.
The court found that Hayb shot Hurndall wilfully while the photographer was helping Palestinian children to take cover from Israeli gunfire in Gaza in 2003. Hurndall died in London in January 2004, after having lain in a coma for nine months.