Mariyappan, a Rio 2016 gold medallist, settled for bronze with a season's best performance of 1.80 metres which was 0.6 metres lower than the champion Sam Grewe's Championship record of 1.86 metres on Thursday.
Sharad, the former world no. 1, stayed in the lead initially, clearing the bar at 1.83 m before Grewe surged ahead with 1.86 m to be on top.
"Athletics is such a sport that everything happens in last moment. I am disappointed with what I performed today. Considering that I have been living and training in Ukraine for the last three years; faced the harsh conditions, I should have given a better performance. I need to re-check my schedule, my planning and many other things," Sharad told Paralympic Committee of India.
"It's been a hard time. I have been playing continuously. Now I need a break. I am going on a holiday from here with my friends who have come down to cheer for me from London," said the 27-year-old, who has completed his Masters in International Relations from Jawaharlal Nehru University in New Delhi.
Mariyappan, who failed to clear 1.83 metres in his last attempt, later admitted that he couldn't perform his best. "My body didn't open up. I didn't get my best one here. The conditions were a little cold in the evening. I hope I can do better in Tokyo 2020 and live up to the expectations of my coach, Satyanarayana," he said.
Also performing in the same event was Ramsingh Padhiya, who settled for fifth place with an effort of 1.77 metres.
Earlier in the day, Lal Vinay Kumar, the Asian Para Games bronze medallist, claimed the bronze in men's 400 m T44 event, and a Tokyo 2020 spot, finishing the crossing line in 55.49 seconds.
After the penultimate day's action, India has nine medals two gold, two silver and five bronze from the Championships. China lead the medals tally with 53 medals including 23 gold medals, followed by Brazil (37) and Great Britain (24).
( With inputs from IANS )