After a month-long investigation, the OPP said Linda O'Leary, 56, has been charged with careless operation of a vessel under the Canada Shipping Act.
Susanne Brito, 48, a mother of three from Uxbridge, Ont., died in hospital the following Tuesday.
A NY man operating the other boat, Richard Ruh, 57, has also been charged with failing to exhibit navigation lights.
Kevin O'Leary driving one of his boats on Lake Joseph back in 2013.
'Shark Tank' star Kevin O'Leary's wife charged in fatal crash
Linda and Kevin O'Leary are seen in this photo.
Ms. O'Leary is set to appear in court October 29.
The two boats reportedly collided on Lake Joseph near Emerald Island at about 11:30 p.m. on August 24.
Never miss the latest news from the Star.
Rebekah Neumann will reportedly step down from roles and titles at WeWork
We scrapped plans for an initial public offering last month after investors balked at the company's sky-high valuation. They were also unnerved by deals We Co. reached with Neumann and entities he controlled.
". but we find it regrettable that the OPP has chosen to charge Mrs".
Three other people suffered injuries as well; all were treated and released from the hospital.
Linda O'Leary's lawyer, Brian Greenspan, said his client was driving home "on a dark and moonless night" with the boat's lights on "at a reasonable speed" when it collided with the other boat.
Ruh did not immediately respond to a request for comment. "I am fully cooperating with authorities", Kevin said in a statement at the time.
Petrol, diesel prices rise for 6th day straight
While Yemen's Iranian-allied Houthi rebels claimed the assault, Saudi Arabia says it was "unquestionably sponsored by Iran". The crude oil rates saw on of its biggest single-day jump on September 16 after Saudi Arabia drone attack.
Both boats left the scene to get help, Carolle Dionne, media relations officer for the OPP, said.
"My heartfelt prayers and condolences to the victims, the families and those affected by this loss", he added. O'Leary is cooperating with law enforcement in their investigation into this tragedy.
Kevin O'Leary and his wife Linda O'Leary were not available for immediate comments, while Ruh could not be reached.
O'Leary stars in the ABC show "Shark Tank".
'Undeniable': Saudi Arabia says remnants of drones show Iran link to attack
In a statement Wednesday, Saudi Arabia's Ministry of Foreign Affairs said the weapons used in the attack were "Iranian". The new stage of the long-running US-Iranian standoff has raised speculation over whether it will lead to conflict.
O'Leary, a Canadian businessman, author and TV personality, campaigned for the leader of the Conservative Party of Canada in 2017.