The Mostyn Medal is an annual award given in the AFL Sydney. Named after Sam Mostyn, the first ever female AFL Commissioner, the medal is awarded to best and fairest player of the Women's Premier Division competition each year.

The award was first awarded in 2012 when the Sydney Women's AFL came under the umbrella of AFL Sydney, and was named the Mostyn Medal in 2015. The medal is named after Sam Mostyn, the first ever female AFL Commissioner.

It has been awarded annual since then, except in 2021, due to the cancellation of the 2021 AFL Sydney season due to the COVID-19 outbreak across Greater Sydney.

It is awarded to best and fairest player of the Women's Premier Division competition each year

At the completion of each match, the field umpires combine to cast votes for the three best players on the ground in a 3-2-1 format. The player with the most votes at the end of the season is considered the Best and Fairest player and is awarded the Mostyn Medal.