How to use SVG markers in Google Maps API v3

You can render your icon using the SVG Path notation.

See Google documentation for more information.

Here is a basic example:

var icon = {

    path: "M-20,0a20,20 0 1,0 40,0a20,20 0 1,0 -40,0",
    fillColor: '#FF0000',
    fillOpacity: .6,
    anchor: new google.maps.Point(0,0),
    strokeWeight: 0,
    scale: 1
}

var marker = new google.maps.Marker({
    position: event.latLng,
    map: map,
    draggable: false,
    icon: icon
});

Here is a working example on how to display and scale a marker SVG icon:

JSFiddle demo

Edit:

Another example here with a complex icon:

JSFiddle demo

Edit 2:

And here is how you can have a SVG file as an icon:

JSFiddle demo