The number 666 and an upside down cross was spray-painted on the door of the temple in Old Lake Highlands, north Texas.
Krishna Singh, who is on the temple's board, said they discovered the graffiti on Monday.
"That was a big shock, really...The whole things has been very disturbing to the community," CBS Local quoted Singh as saying.
Dallas police sent out detectives with the gang unit who are still searching for suspects.
Now devotees will build a fence around the entire property to keep vandals out.
Both Hindus and non-Hindus have offered to help the temple clean the damage.
This is the third such incident in three months. Two temples were vandalised in Washington State in February.
On February 15, unidentified miscreants sprayed swastika and painted "Get Out" on one of the walls of the Bothell Hindu Temple in the Seattle Metropolitan area.
On February 26, vandals used bricks to break several windows and then painted the word "fear" on the wall of the Kent Hindu Temple.
Image used for representational purposes only
Another Hindu temple vandalised in US
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