RCMP say Zhongming "James" Mou admitted Tuesday in B.C. Supreme Court to second-degree murder in the death of 27-year-old Yating "Lancy" Hu.
Mou was initially charged with first-degree murder.
Hu's body was found in the river off Richmond in August 2011.
She vanished a month earlier, and Mou gave police conflicting stories about her disappearance.
Sgt. Jennifer Pound said the determination of investigators was paramount in bringing justice in the horrific case.
“Lancy Hu is missed by her family, including her parents and her young boys," she said.
"This tragedy will require endless healing for those who loved her."
The couple's boys are now in the care of their grandparents.