From a fiqhi perspective, reading the Quran’s translation doesn’t count as the recitation of the Quran itself and it is for this reason that the ulema have stated: “Touching the writing of the Quran with any part of the body is haram for one who doesn’t have wudu. But if it has been translated to Farsi or any other language, touching the translation isn't problematic.”[1] They have also said: “One must learn to recite the prayer without mistakes.”[2] Therefore, one cannot substitute the recitation of surahs Hamd and the other surah with their translations.

Also, content-wise, no matter how close translations get to the real meaning of the Quran, they still can't match it. That is why learning Arabic for better understanding of the Quran is very good and holds precedence over other things, nevertheless this doesn’t mean that reading its translation has no benefit. On the contrary, use of these translations is beneficial to those who don’t know Arabic.
[1] Tawdihul-Masa’el (annotated by Imam Khomeini), vol. 1, pg. 186.
[2] Tawdihul-Masa’el (annotated by Imam Khomeini), vol. 1, pg. 550.

Source: slamquest