In 1996, Colao joined Omnitel Pronto Italia, which subsequently became Vodafone Italy, and he was appointed Chief Executive in 1999.
Colao has been in the hot seat since 2008, overseeing a period of transformation which has seen the business reorient itself from a consumer focussed mobile operator into a communications empire operating the largest mobile and fixed-generation network in Europe.
Over the past 10 years, Colao has been instrumental in reshaping the group and widening its mobile customer base to 536 million, from 269 million, across 25 countries.
His replacement, Read, became Vodafone's CFO in April 2014, having previously worked as the group's chief executive for the Africa, Middle East and Asia Pacific region.
Della Valle was appointed Deputy Group Chief Financial Officer in 2015.
"Vittorio (Colao) decided the time was right - after 10 years as CEO, 14 on the Board, and 20 years at Vodafone - to hand over the reins", a Vodafone spokesperson said. "Vittorio will leave as his legacy a company of great integrity with strong inclusive values that is exceptionally well-positioned for the decade ahead".
Vodafone group chairman Gerard Kleisterlee remarked: "Nick has been the co-architect of the Group's strategy together with Vittorio, combining extensive worldwide operational and commercial leadership with world-class financial acumen".
Following the news, shares in Vodafone fell nearly 4 per cent.
Colao was appointed Chief Executive Officer of the UK-based group in July 2008- nearly a year after Vodafone brand was launched in India.
Vodafone Group said Nick Read will be the next CEO of the company, succeeding Colao.
Vodafone India today posted operating profit of Rs 9,805 crore for the fiscal ended March 2018, largely on the back of Rs 3,850 crore gains from the sale of mobile towers. Groupwide revenues dipped 2.2% to €46.6bn (£40.99bn), due in part to the December 2016 deconsolidation of its Dutch business and in part to foreign currency movements.
"This was a year of significant operational and strategic achievement and strong financial performance", said Colao.
"Our sustained investment in network quality supported robust commercial momentum", he added.
Excluding the negative impact of net roaming declines in Europe, the benefits of settlements in the United Kingdom and Germany and the introduction of handset financing in the United Kingdom, organic adjusted EBITDA grew by 7.9%.
His exit comes just ahead of Vodafone India's merger with Idea Cellular.