The pair welcomed their twins in 2015 after reportedly dating for two years when Mikel was playing for Chelsea.
Mikel, who joined Chinese club Tianjin TEDA in a reported £140,000-a-week deal in January, allegedly has a secret son and daughter by two different women in the UK.
It was not clear why the 30-year-old South Africa 2013 Africa Cup of Nations winner decided to take down the pictures, but there are feelers that the duo have endured a frosty relationship in recent times.
Olga copped a lot of flak from some Nigerian girls in March after she posted the picture of herself and her boyfriend on Instagram.
The Russian’s critics, in their various comments, insisted that Mikel could have made a better choice in Nigeria.