Rosales joined Star Circle 4 in 1997. On the small screen, he was featured in several Maalaala Mo Kaya episodes, Pangako sa 'Yo, Sana'y Wala Nang Wakas and Ang Panday. The telenovela Pangako sa 'Yo made him a common household name, not only in the Philippines, but also in other South East Asian Countries as well, such as Malaysia.
Rosales starred in the critically-acclaimed films Tanging Yaman, Bagong Buwan, Noon at Ngayon, Santa Santita, and Nasaan Ka Man. He was also the other-half of the hugely popular loveteam with Kristine Hermosa in Trip, Forevermore, and Ngayong Nandito Ka. His latest movie was the true-to-life story of the famous Filipino boxer Manny Pacquiao.
In March 2006, EMI Malaysia signed Rosales and his band Jeans (in which he is the lead singer and songwriter) for their debut album Loose Fit. In June 2006, Rosales and ex-girlfriend Heart Evangelista began endorsing one of the Philippines' leading fashion apparel brand Penshoppe.
In 2008, The largest integrated media and entertainment company in the Philippine, ABS-CBN Broadcasting Crop. has signed a contract with Malaysian production outfit Double Vision.The two companies agreed to co-produce a TV series which will be topbilled by awarded Filipino actor [Jericho Rosales] and [Malaysian superstar] and model Carmen Soo.
In May 2008, He and Heart became one of the controversy issues in the Entertainment. After 3 years of romance, Heart decided to end their relationship via Television. Heart, who made a via patch interview, revealed that the reason she broke-up with Jericho is because she caught him having an affair with Hollywood actress Briana Evigan. He and Briana also worked together in the Hollywood film Subject:I Love You. Jericho "Echo" Rosales on May 11, 2008, admitted on The Buzz his inner turmoil, and that he's still in denial over Heart breaking up with him due to influence and false accusations by some people: "I'm full of Heart right now. Heart is written all over my whole personality and character.I know how parents are, and I'm touched how much Heart’s parents love her. They have wonderful dreams for Heart and I'm sorry that our relationship got in the way of their dreams for her."