Last week Trump said Esper would be appointed acting defence secretary after the surprise resignation by then acting secretary, Patrick Shanahan.
Shanahan was also nominated for the permanent spot but withdrew himself after reports surfaced about past incidents of domestic violence against his ex-wife.
If he is confirmed, Esper will replace Jim Mattis, who resigned in December, days after Trump made the widely-criticized decision to withdraw troops from Syria.
Esper's nomination comes as the US is in the midst of escalating tensions with Iran over Tehran's downing of a US drone.
The incident nearly led the US to strike Iran on Thursday, until Trump called of the attack after initially approving it.
Esper is a graduate of the elite military academy West Point and a former lobbyist for defence contractor Raytheon.
Shanahan was also nominated for the permanent spot but withdrew himself after reports surfaced about past incidents of domestic violence against his ex-wife.
If he is confirmed, Esper will replace Jim Mattis, who resigned in December, days after Trump made the widely-criticized decision to withdraw troops from Syria.
Esper's nomination comes as the US is in the midst of escalating tensions with Iran over Tehran's downing of a US drone.
The incident nearly led the US to strike Iran on Thursday, until Trump called of the attack after initially approving it.
Esper is a graduate of the elite military academy West Point and a former lobbyist for defence contractor Raytheon.