The 54-year-old model explained that the legendary musician's grave does not yet have a headstone because her two sons with Ocasek, Oliver, 26, and Jonathan, 21, are in the process of designing it.
The touching photo showed Oliver crouching down in front of a small mushroom-shaped figurine in the grass.
"A simple little mushroom taken off our porch, for now, marks the resting place of their dad," Porizkova wrote.
"The real thing is being designed jointly by both of them: a fitting tribute to the father they adored," she continued in the post. "Thank you my darling Oliver for letting me share this private moment. #missdad #loveneverdies #ricocasekrip"
Porizkova's tribute to Ocasek comes after the model opened up about her grief following his death last month. At the time, Porizkova told her fans she was "not good" and still "angry" over her loss.
"I'm breaking under the weigh to fit all," she told her over 100,000 Instagram followers.
Ocasek died on Sept. 15 at the age of 75. The rock legend, whose band helped define the sound of rock music in the late 1970s and '80s, died from hypertensive and atherosclerotic cardiovascular disease, according to the New York City medical examiner.
Pulmonary emphysema was also a contributing factor, the medical examiner revealed. His manner of death was ruled natural.