The ruling is the fourth tough sentence to be handed down in the Sunni-ruled Gulf kingdom in less than a week.
It brings to 95 the number of Shiites jailed in five days in relation to violent incidents, despite criticism from rights watchdog Amnesty International.
The four men -- two of whom were tried in absentia -- were charged with "attempting to murder a man (the Asian worker) and policemen by placing a roadside bomb between large rocks in the village of Dair," the source said.
The attack in the village near the capital, in which the worker's arm was wounded, took place on March 17.
On Wednesday, four Shiites were jailed for 15 years each after being convicted of detonating a bomb that also wounded an Asian worker in Manama,
And on Monday, 37 others were jailed for up to 15 years after being convicted of "terrorist crimes".
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A court on Sunday also handed jail terms of up to 15 years to 50 activists, including a prominent Shiite Iraqi cleric, for forming a clandestine opposition group.
Rights group Amnesty slammed the ruling as appalling and demanded a probe into allegations that some of the activists had been tortured.
In August, King Hamad decreed stiffer penalties for "terror acts" in the country rocked by Shiite-led Arab Spring-inspired protests since March 2011.
These include a minimum 10-year jail term for an attempted bombing. If casualties result, the sentence can be life imprisonment or the death penalty.
Bahraini Shiites continue to demonstrate in villages outside the capital and frequently clash with police.
At least 89 people have been killed since the protests began two and a half years ago, according to the International Federation for Human Rights.
Strategically located across the Gulf from Shiite Iran, Bahrain is home to the US Navy's Fifth Fleet and is an offshore financial and services centre for its oil-rich Gulf Arab neighbours.