malaysian going to china for travel need to apply visa ? where is there embasy in johor bahru?

Yes, you need to apply for a China tourist visa in advance. Passport holders from Sarawak, Sabah, Labuan should submit application to Consulate-General of the People's Republic of China in Kuching.
But if your place does not belong to Sarawak, Sabah, Labuan, you need to submit your applicaiton to CVASC at 2nd Floor, Plaza OSK, 25 Jalan Ampang, 50450 Kuala Lumpur.