My last trip in China was April 26 and I have a Z visa. Now, I am planning to come to China on July.

Do you mean that your former China Z visa has expired? If yes, you shoudl apply for a new visa if you plan to go to China again. The requirements for a China tourist visa include your valid passport, truly filled China visa application form, a recent-taken colored photo with white background, full-face front view and no hat, previously used China visa stickers in old or new passport, photo copy of the emergency contact information page in your passport, two-way air ticket and hotel booking in China.

Hi! Have you had applied for the tourist Visa yet? And does anyone knows if i need to submit invitation letter again if plan to travel to China again,,, lets say for second timer?