MEXICO CITY, July 22 (Reuters) - Walmart's Mexico unit on Thursday reported second quarter net profit of 9.8 billion pesos ($489.5 million), up from the year-earlier period, when the retailer posted net profit of 1.6 billion pesos.

Walmart de Mexico, the biggest retailer in Mexico, brought in revenue of 174.7 billion pesos in the quarter, 3.3% more than the April to June period a year ago.

($1 = 19.9470 pesos at end-June) (Reporting by Daina Beth Solomon and Noe Torres Editing by Chris Reese)