The 24-year old, who made headlines when he scored a hat-trick on international debut against Yemen to lead his country to a 3-2 victory in January, is desperate to make Takeshi Okada's Blue Samurai team but says he is not getting carried away with anything just yet.
"I really want to go to the World Cup, but I'm not taking anything for granted," Hirayama told The Japan Times.
"If I don't get picked I'm sure I'll be disappointed and it will hurt, but I can still play football and there is always another World Cup in four years. I also have ambitions that I want to fulfill with my club, and if I don't make it, I will just have to work harder.
"But my height is an advantage. Other teams might be expecting the Japanese players all to be short, so it's in my favour that I'm tall."
"Goals are the best medicine for a striker," he added. "No matter what shape you're in, if you score it gives you confidence. If you have confidence, you play in a positive frame of mind. That's a very important thing."