The state ceremony, held on Israel's national day of mourning to commemorate fallen soldiers, security forces members and terror victims, was attended by top Israeli officials, including President Reuven Rivlin.
The prime minister's remarks come amid escalating tensions between Israel and Iran over an alleged Israeli airstrike targeting a Syrian air force base last week.
"Anyone who raises a hand against us won't be spared," Netanyahu warned.
"If we're required to defend ourselves, we will rise to the challenge and ensure Israel's victory," he added later at an Independence Day ceremony, as Memorial Day came to a close and the country's 70th anniversary celebration began.
Netanyahu kindled an Independence Day torch in the name of Israel's governments throughout its 70-year history.
Following the alleged attack, which claimed the lives of seven Iranian nationals, a senior adviser to Iran's Supreme Leader Ayatollah Ali Khamenei warned that the strikes wouldn't "go unanswered." Meanwhile, Sky News Arabia reported, citing an IDF official, that Israel would retaliate if Iran decided to strike back for the incident at the T-4 airbase.