Before becoming an MP, he was a local councillor in Romford on Havering Council, winning the Chase Cross and Havering-atte-Bower ward from the Liberal Democrats in 1990 with a 25% swing.

[8] Rosindell stood in Thurrock at the 1997 general election, coming second with 26.8% of the vote behind the incumbent Labour MP Andrew MacKinlay.

[10] Former Conservative Prime Minister Margaret Thatcher visited the constituency during the campaign, in which Rosindell also canvassed with his Staffordshire Bull Terrier Spike, who wore a union flag waistcoat.

In February 2015, Rosindell cast doubt on the ability of Rachel Reeves (then Shadow Secretary of State for Work and Pensions) to handle that ministerial responsibility in a potential post-election Labour cabinet, as she would be taking maternity leave soon after the election and would then have a young child to care for following her return to the post in September.

He was criticised for the remarks by Labour MPs, whilst Conservative leader and Prime Minister David Cameron described his comments as "outrageous".

[26][27] In June 2018, Rosindell co-sponsored a Bill with Lord Empey to use Libyan funds frozen under Chapter 7 of the UN Charter, to compensate victims of IRA terrorism supported by the Gaddafi regime.

[30] In January 2019, The Times discovered that Rosindell's Facebook account was a member of a group supporting far-right activist Tommy Robinson.

[32][33] On 21 October 2020, Rosindell was removed as trade envoy to Tanzania, a position to which he had been appointed to by Theresa May in 2018, because of his highly critical views against Boris Johnson's three-tier lockdown plan to tackle the second wave of the coronavirus pandemic in the UK.

"[35] Politico reported in December 2022 that Rosindell was among a small group of about ten backbench MPs who have made a large number of overseas visits while in office.

Rosindell's political views are socially conservative and Thatcherite: he is a Eurosceptic, who supports the re-introduction of the death penalty and the detention of asylum seekers.

Following an interim report on the connections between colonialism and properties now in the care of the National Trust, including links with historic slavery, Rosindell was among the signatories of a letter to The Telegraph in November 2020 from the "Common Sense Group" of Conservative Parliamentarians.

He has said, "I do not believe that politicians should interfere with and attempt to redefine ancient customs, traditions and ceremonies, most of which are based on religious foundations and have been in existence through the ages.

"[42] In 2012, Rosindell unsuccessfully attempted to introduce the United Kingdom Borders Bill, a private member's bill aiming to create a dedicated entry queue for citizens of countries where the British Queen is head of state, as well as introducing pictures of the Queen and more royal symbols at UK borders.

The speech also advocated a policy of controlled immigration, arguing that public services were unable to keep up with the number of people entering the country every year.

"[52] In July 2010, Rosindell was appointed by the Chairman of the Conservative Party, Sayeeda Warsi, onto the board of the Westminster Foundation for Democracy.

In April 2021 Rosindell joined other Conservative Party members in calling for the Union Flag to be flown outside UK schools.

[63] A spokesperson for Rosindell stated that "He has been working constantly for Romford throughout the past 21 months and will continue to speak up for the people of his beloved home town as their local MP.