Disneyland rarely rents out the entire park for a whole day, because they would lose money to do so. It's estimated that Disneyland makes about $3 million per day after expenses. So it would not be worth it for them to rent out the whole park for a day, unless someone was willing to pay about $5 million.
Exact prices are not available online, but some have stated in online forums that Disneyland can be rented for an evening only for about $1 million. It's also been estimated that one land in the park can be rented for about $250,000.
For those not wishing to spend as much, only one attraction can be rented, with the price estimated at about $10,000 per hour. If interested in renting Disneyland or a portion of it, it's advised to call Disneyland Resort Group Sales for more information at (714) 520-7025.
Of interest, in 2015, Kanye West and Kim Kardashian have rented out Disneyland to celebrate their daughter North’s second birthday. The Wests have made arrangements to rent out the entirety of the Anaheim, California located theme park for the day, meaning that only the special VIPs will be allowed into Disneyland on the big day.