Keith Wilkinson claimed he did not "accentuate the negative and eliminate the positive" about fans' behaviour in a second statement in 1990.
In his first statement nine days after the 1989 disaster, he made no reference that his horse could have been hit.
The Merseyside Police officer said his first statement was the most accurate.
Mr Wilkinson told the inquest jury in Warrington on Thursday no-one told him to make the alterations.
Ninety-six fans died following a crush during the Liverpool v Nottingham Forest FA Cup semi-final in Sheffield.
Mr Wilkinson's second statement in January 1990 included detail about some fans at the side of the road drinking from cans and bottles.
There was a claim about his horse potentially being hit on the head.
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He was one of 14 mounted officers from Merseyside Police who was sent to police the match on 15 April 1989.
Peter Wilcock QC, who represents a group of the Hillsborough families, said the inquests would hear evidence that "a number of Merseyside Police officers" all made "second statements" on the same day in January 1990.
Mr Wilkinson, who was on duty at the Leppings Lane end, said he did not remember the second statement.
Mr Wilcock asked: "Is it the case - you have been encouraged by others to accentuate the negative and eliminate the positive as far as the behaviour of Liverpool fans was concerned on that day?"
"That is not the case," Mr Wilkinson replied.
A reference to "no hostility" from fans who were asked to move from a bridge was also removed, the jury was told.
Mr Wilcock asked Mr Wilkinson whether his first statement was inaccurate and if he had "overemphasised how nice they were" and "not emphasised how much they were drinking".
Mr Wilkinson replied: "That's not the case."
He said he could not remember when the second statement was made and for what reason, the coroner heard.
Mr Wilkinson added his first statement was the most accurate and denied he was told to make alterations to his second.
The inquests continue.
Correction 19 September: Keith Wilkinson's evidence was heard on Thursday afternoon. BBC News Online's report on Thursday did not contain this material and a new story was published as soon as this oversight came to light.
A former police officer has denied changing his statement to include more references to fans drinking, the Hillsborough inquests heard.