"A dream that comes true", she writes on Instagram.
The Montreal forward equalized to 3-3 in the third period in the away game against Toronto in front of 8,251 spectators.
The goal saved overtime for Montreal, which then decided through Laura Stacey.
Ljungblom's goal was her first point for Montreal in her fourth match.
Also, national team defender Anna Kjellbin contributed for Montreal and made an assist.
Two more Swedes are in the PWHL, defender Maja Nylén Persson in New York and goalkeeper Emma Söderberg in Boston.
The 23-year-old Skövde product Ljungblom is playing her first season in the PWHL and was last season named Player of the Year in Sweden and the SDHL's best player.
