FORTUNE — Dear Annie:  I just got passed over for yet another promotion, the third one in five years, even though I’ve been working flat-out and all my performance evaluations have been great. This is upsetting, but perhaps not surprising, considering that I am Asian American (third-generation Chinese) and there is no one of Asian extraction in any high position at this company. I hate to “play the race card,” but given the circumstances, I can’t help wondering if there is some subtle race discrimination at work here. What are your thoughts? — Invisible Man

Dear I.M.:  You aren’t the only one wondering. About 5% of U.S. residents identify themselves as Asian, but Asian Americans hold fewer than 2% of executive jobs at Fortune 500 companies, according to a study published in July by the nonprofit Center for Work-Life Policy.

The gap clearly isn’t due to a lack of education: 16% of all Ivy League college grads identify as Asian or Asian American (over three times the group’s representation in the population overall), and more than one-third (35%) of students at top schools like M.I.T. and Stanford identify as Asian or Asian American.

Granted, every now and then someone who identifies as Asian or Asian American scales the corporate heights, like Andrea Jung, CEO of Avon Products (AVP), and Citigroup (C) chief Vikram Pandit. Altogether, eight Fortune 500 CEOs identify themselves as Asian.

Partly for that reason, about one-quarter of Asian people surveyed for the CWLP study said they believe that race discrimination is holding them back at work. Interestingly, a scant 4% of Caucasians saw any evidence of bias against Asian people.

So what gives?

Human resources consultant Jane Hyun says that some Asian cultures encourage an ethic that rewards hard work without seeking public recognition. “’But hard work alone isn’t enough,” says Hyun, who runs an executive coaching firm called Hyun & Associates and is the author of Breaking the Bamboo Ceiling: Career Strategies for Asians. “Asian cultures have sayings like ‘The loudest duck gets shot,’” Hyun observes. “This is totally opposite from, and incompatible with, Western notions like ‘The squeaky wheel gets the grease.’”

Michael Hyter, author of a new book called The Power of Choice, agrees. As head of Boston-based consulting firm Global Novations, he has noticed in his work with American and Asian clients that “there is a real cultural disconnect.

“Americans are taught to show leadership potential by being gregarious, outgoing, outspoken, and confident, but the Asian ideal is to work very hard, be humble and deferential, and blend in with the group. Expressing opinions or proposing changes is often seen [in Asia] as disrespectful.”

About half (48%) of respondents to the CWLP survey said the biggest hurdle Asian Americans face is “conformity to prevailing leadership models.”

Says Hyter, “It’s important to take a close look at who is getting promoted at your company and analyze what they’re doing, besides working hard. You need to understand how your company defines leadership qualities.”

He notes that technical skills are the easiest kind to identify and measure, so “they tend to be how we evaluate our own performance. But, although no one talks about it, promotions are 85% based on other skills, like the ability to influence others and form strategic relationships.”

You don’t have to go it alone. Hyter, a former executive at Dayton Hudson (now Target) who happens to be African-American, says his own parents instilled in him the idea that “getting good grades and out-working everyone else would make me successful,” he recalls. “Then I noticed that alone was not doing it. Luckily, I had a mentor who helped me figure out the unwritten rules.”

You need one too. “It should be someone at least two levels above you in the organization,” Hyter says. “Ask for feedback about what you need to work on.”

At the same time, both Hyun and Hyter urge you to expand your network and boost your visibility by seeking out “opportunities to lead projects and influence people,” Hyter says. “It requires you to stretch a little — without losing sight of who you are.”