The Twitter profile in question has Arjun's action image as profile photo and an image of him at the Lord's as the cover photo.
"Official. Left Arm Medium Pacer. Son of God," reads the account's bio. According to Twitter, the account has been active since June 2018.
Tendulkar confirmed that neither Arjun nor his daughter Sara are on Twitter.
The sporting icon wrote on his Twitter handle @sachin_rt: "I wish to clarify that my son Arjun & daughter Sara are not on Twitter.
"The account @jr_tendulkar is wrongfully impersonating Arjun and posting malicious tweets against personalities & institutions. Requesting @TwitterIndia to act on this as soon as possible."
The post got 2.2K retweets and 20K likes.
One fan wrote: "That's ridiculous what weirdos would create a fake account to impersonate a child? Pathetic."
One user reminded Tendulkar that frauds happen everywhere. "No one can stop this, that is the reality, isn't it?"
"Who had the temerity to target God's family? Twitter India should take this seriously," read another post.
Many fans expressed support and urged Twitter officials to take action. They also wrote that they had since reported the fake account.
One fan suggested that the master blaster should create new official Twitter handles for both siblings. "Automatically the fake ones will be exposed," he reasoned.
Others said Twitter had suspended the account. One fan wrote: "As the God requested, Twitter acted immediately and removed the fake account!@sachin_rt".
Arjun bowls left-arm medium pace and has represented Mumbai at the U-16 and U-19 levels. The son of the legendary batsman was selected for Mumbai seniors team for a pre-season tournament earlier this year.
( With inputs from IANS )