A plastic lens assembly includes at least two plastic lens elements and at least one cementing glue coating. The plastic lens elements include a first plastic lens element and a second plastic lens element. The first plastic lens element has a first optical effective portion and a first peripheral portion, wherein the first peripheral portion surrounds the first optical effective portion. The second plastic lens element has a second optical effective portion and a second peripheral portion, wherein the second peripheral portion surrounds the second optical effective portion. The cementing glue coating is disposed between the first optical effective portion and the second optical effective portion, and for cementing the first plastic lens element and the second plastic lens element, wherein at least one optical gap is formed between the first optical effective portion and the second optical effective portion.